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authorLinus Torvalds <torvalds@linux-foundation.org>2013-05-02 14:38:53 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-05-02 14:38:53 -0700
commit99bece775f988a4ee21ad3db9fd413caf1704ff6 (patch)
tree5975cdcd92301e54dfe1424ec5d008898b5c9331 /drivers/i2c
parent736a2dd2571ac56b11ed95a7814d838d5311be04 (diff)
parentc39e8e4354ce4daf23336de5daa28a3b01f00aa6 (diff)
Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c changes from Wolfram Sang: - an arbitration driver. While the driver is quite simple, it caused discussion if we need additional arbitration on top of the one specified in the I2C standard. Conclusion is that I accept a few generic mechanisms, but not very specific ones. - the core lost the detach_adapter() call. It has no users anymore and was in the way for other cleanups. attach_adapter() is sadly still there since there are users waiting to be converted. - the core gained a bus recovery infrastructure. I2C defines a way to recover if the data line is stalled. This mechanism is now in the core and drivers can now pass some data to make use of it. - bigger driver cleanups for designware, s3c2410 - removing superfluous refcounting from drivers - removing Ben Dooks as second maintainer due to inactivity. Thanks for all your work so far, Ben! - bugfixes, feature additions, devicetree fixups, simplifications... * 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (38 commits) i2c: xiic: must always write 16-bit words to TX_FIFO i2c: octeon: use HZ in timeout value i2c: octeon: Fix i2c fail problem when a process is terminated by a signal i2c: designware-pci: drop superfluous {get|put}_device i2c: designware-plat: drop superfluous {get|put}_device i2c: davinci: drop superfluous {get|put}_device MAINTAINERS: Ben Dooks is inactive regarding I2C i2c: mux: Add i2c-arb-gpio-challenge 'mux' driver i2c: at91: convert to dma_request_slave_channel_compat() i2c: mxs: do error checking and handling in PIO mode i2c: mxs: remove races in PIO code i2c-designware: switch to use runtime PM autosuspend i2c-designware: use usleep_range() in the busy-loop i2c-designware: enable/disable the controller properly i2c-designware: use dynamic adapter numbering on Lynxpoint i2c-designware-pci: use managed functions pcim_* and devm_* i2c-designware-pci: use dev_err() instead of printk() i2c-designware: move to managed functions (devm_*) i2c: remove CONFIG_HOTPLUG ifdefs i2c: s3c2410: Add SMBus emulation for block read ...
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-amd756-s4882.c6
-rw-r--r--drivers/i2c/busses/i2c-at91.c58
-rw-r--r--drivers/i2c/busses/i2c-cbus-gpio.c4
-rw-r--r--drivers/i2c/busses/i2c-davinci.c77
-rw-r--r--drivers/i2c/busses/i2c-designware-core.c39
-rw-r--r--drivers/i2c/busses/i2c-designware-pcidrv.c73
-rw-r--r--drivers/i2c/busses/i2c-designware-platdrv.c83
-rw-r--r--drivers/i2c/busses/i2c-gpio.c75
-rw-r--r--drivers/i2c/busses/i2c-intel-mid.c3
-rw-r--r--drivers/i2c/busses/i2c-ismt.c2
-rw-r--r--drivers/i2c/busses/i2c-mv64xxx.c5
-rw-r--r--drivers/i2c/busses/i2c-mxs.c104
-rw-r--r--drivers/i2c/busses/i2c-nforce2-s4985.c6
-rw-r--r--drivers/i2c/busses/i2c-octeon.c10
-rw-r--r--drivers/i2c/busses/i2c-powermac.c10
-rw-r--r--drivers/i2c/busses/i2c-puv3.c10
-rw-r--r--drivers/i2c/busses/i2c-pxa.c20
-rw-r--r--drivers/i2c/busses/i2c-s3c2410.c48
-rw-r--r--drivers/i2c/busses/i2c-tegra.c26
-rw-r--r--drivers/i2c/busses/i2c-viperboard.c5
-rw-r--r--drivers/i2c/busses/i2c-xiic.c6
-rw-r--r--drivers/i2c/i2c-core.c246
-rw-r--r--drivers/i2c/i2c-mux.c9
-rw-r--r--drivers/i2c/muxes/Kconfig12
-rw-r--r--drivers/i2c/muxes/Makefile2
-rw-r--r--drivers/i2c/muxes/i2c-arb-gpio-challenge.c251
-rw-r--r--drivers/i2c/muxes/i2c-mux-gpio.c17
-rw-r--r--drivers/i2c/muxes/i2c-mux-pca954x.c6
28 files changed, 824 insertions, 389 deletions
diff --git a/drivers/i2c/busses/i2c-amd756-s4882.c b/drivers/i2c/busses/i2c-amd756-s4882.c
index 378fcb5d5783..07f01ac853ff 100644
--- a/drivers/i2c/busses/i2c-amd756-s4882.c
+++ b/drivers/i2c/busses/i2c-amd756-s4882.c
@@ -169,11 +169,7 @@ static int __init amd756_s4882_init(void)
}
/* Unregister physical bus */
- error = i2c_del_adapter(&amd756_smbus);
- if (error) {
- dev_err(&amd756_smbus.dev, "Physical bus removal failed\n");
- goto ERROR0;
- }
+ i2c_del_adapter(&amd756_smbus);
printk(KERN_INFO "Enabling SMBus multiplexing for Tyan S4882\n");
/* Define the 5 virtual adapters and algorithms structures */
diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index 75195e3f5ddb..6bb839b688be 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -603,15 +603,18 @@ static const struct of_device_id atmel_twi_dt_ids[] = {
}
};
MODULE_DEVICE_TABLE(of, atmel_twi_dt_ids);
-#else
-#define atmel_twi_dt_ids NULL
#endif
-static bool filter(struct dma_chan *chan, void *slave)
+static bool filter(struct dma_chan *chan, void *pdata)
{
- struct at_dma_slave *sl = slave;
+ struct at91_twi_pdata *sl_pdata = pdata;
+ struct at_dma_slave *sl;
+
+ if (!sl_pdata)
+ return false;
- if (sl->dma_dev == chan->device->dev) {
+ sl = &sl_pdata->dma_slave;
+ if (sl && (sl->dma_dev == chan->device->dev)) {
chan->private = sl;
return true;
} else {
@@ -622,11 +625,10 @@ static bool filter(struct dma_chan *chan, void *slave)
static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr)
{
int ret = 0;
- struct at_dma_slave *sdata;
+ struct at91_twi_pdata *pdata = dev->pdata;
struct dma_slave_config slave_config;
struct at91_twi_dma *dma = &dev->dma;
-
- sdata = &dev->pdata->dma_slave;
+ dma_cap_mask_t mask;
memset(&slave_config, 0, sizeof(slave_config));
slave_config.src_addr = (dma_addr_t)phy_addr + AT91_TWI_RHR;
@@ -637,25 +639,22 @@ static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr)
slave_config.dst_maxburst = 1;
slave_config.device_fc = false;
- if (sdata && sdata->dma_dev) {
- dma_cap_mask_t mask;
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
- dma_cap_zero(mask);
- dma_cap_set(DMA_SLAVE, mask);
- dma->chan_tx = dma_request_channel(mask, filter, sdata);
- if (!dma->chan_tx) {
- dev_err(dev->dev, "no DMA channel available for tx\n");
- ret = -EBUSY;
- goto error;
- }
- dma->chan_rx = dma_request_channel(mask, filter, sdata);
- if (!dma->chan_rx) {
- dev_err(dev->dev, "no DMA channel available for rx\n");
- ret = -EBUSY;
- goto error;
- }
- } else {
- ret = -EINVAL;
+ dma->chan_tx = dma_request_slave_channel_compat(mask, filter, pdata,
+ dev->dev, "tx");
+ if (!dma->chan_tx) {
+ dev_err(dev->dev, "can't get a DMA channel for tx\n");
+ ret = -EBUSY;
+ goto error;
+ }
+
+ dma->chan_rx = dma_request_slave_channel_compat(mask, filter, pdata,
+ dev->dev, "rx");
+ if (!dma->chan_rx) {
+ dev_err(dev->dev, "can't get a DMA channel for rx\n");
+ ret = -EBUSY;
goto error;
}
@@ -785,12 +784,11 @@ static int at91_twi_probe(struct platform_device *pdev)
static int at91_twi_remove(struct platform_device *pdev)
{
struct at91_twi_dev *dev = platform_get_drvdata(pdev);
- int rc;
- rc = i2c_del_adapter(&dev->adapter);
+ i2c_del_adapter(&dev->adapter);
clk_disable_unprepare(dev->clk);
- return rc;
+ return 0;
}
#ifdef CONFIG_PM
@@ -828,7 +826,7 @@ static struct platform_driver at91_twi_driver = {
.driver = {
.name = "at91_i2c",
.owner = THIS_MODULE,
- .of_match_table = atmel_twi_dt_ids,
+ .of_match_table = of_match_ptr(atmel_twi_dt_ids),
.pm = at91_twi_pm_ops,
},
};
diff --git a/drivers/i2c/busses/i2c-cbus-gpio.c b/drivers/i2c/busses/i2c-cbus-gpio.c
index 98386d659318..1be13ac11dc5 100644
--- a/drivers/i2c/busses/i2c-cbus-gpio.c
+++ b/drivers/i2c/busses/i2c-cbus-gpio.c
@@ -206,7 +206,9 @@ static int cbus_i2c_remove(struct platform_device *pdev)
{
struct i2c_adapter *adapter = platform_get_drvdata(pdev);
- return i2c_del_adapter(adapter);
+ i2c_del_adapter(adapter);
+
+ return 0;
}
static int cbus_i2c_probe(struct platform_device *pdev)
diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c
index 7d1e590a7bb6..cf20e06a88e1 100644
--- a/drivers/i2c/busses/i2c-davinci.c
+++ b/drivers/i2c/busses/i2c-davinci.c
@@ -137,7 +137,7 @@ static inline u16 davinci_i2c_read_reg(struct davinci_i2c_dev *i2c_dev, int reg)
}
/* Generate a pulse on the i2c clock pin. */
-static void generic_i2c_clock_pulse(unsigned int scl_pin)
+static void davinci_i2c_clock_pulse(unsigned int scl_pin)
{
u16 i;
@@ -155,7 +155,7 @@ static void generic_i2c_clock_pulse(unsigned int scl_pin)
/* This routine does i2c bus recovery as specified in the
* i2c protocol Rev. 03 section 3.16 titled "Bus clear"
*/
-static void i2c_recover_bus(struct davinci_i2c_dev *dev)
+static void davinci_i2c_recover_bus(struct davinci_i2c_dev *dev)
{
u32 flag = 0;
struct davinci_i2c_platform_data *pdata = dev->pdata;
@@ -166,7 +166,7 @@ static void i2c_recover_bus(struct davinci_i2c_dev *dev)
flag |= DAVINCI_I2C_MDR_NACK;
/* write the data into mode register */
davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag);
- generic_i2c_clock_pulse(pdata->scl_pin);
+ davinci_i2c_clock_pulse(pdata->scl_pin);
/* Send STOP */
flag = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG);
flag |= DAVINCI_I2C_MDR_STP;
@@ -289,7 +289,7 @@ static int i2c_davinci_wait_bus_not_busy(struct davinci_i2c_dev *dev,
return -ETIMEDOUT;
} else {
to_cnt = 0;
- i2c_recover_bus(dev);
+ davinci_i2c_recover_bus(dev);
i2c_davinci_init(dev);
}
}
@@ -379,7 +379,7 @@ i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop)
dev->adapter.timeout);
if (r == 0) {
dev_err(dev->dev, "controller timed out\n");
- i2c_recover_bus(dev);
+ davinci_i2c_recover_bus(dev);
i2c_davinci_init(dev);
dev->buf_len = 0;
return -ETIMEDOUT;
@@ -643,7 +643,7 @@ static int davinci_i2c_probe(struct platform_device *pdev)
{
struct davinci_i2c_dev *dev;
struct i2c_adapter *adap;
- struct resource *mem, *irq, *ioarea;
+ struct resource *mem, *irq;
int r;
/* NOTE: driver uses the static register mapping */
@@ -659,24 +659,18 @@ static int davinci_i2c_probe(struct platform_device *pdev)
return -ENODEV;
}
- ioarea = request_mem_region(mem->start, resource_size(mem),
- pdev->name);
- if (!ioarea) {
- dev_err(&pdev->dev, "I2C region already claimed\n");
- return -EBUSY;
- }
-
- dev = kzalloc(sizeof(struct davinci_i2c_dev), GFP_KERNEL);
+ dev = devm_kzalloc(&pdev->dev, sizeof(struct davinci_i2c_dev),
+ GFP_KERNEL);
if (!dev) {
- r = -ENOMEM;
- goto err_release_region;
+ dev_err(&pdev->dev, "Memory allocation failed\n");
+ return -ENOMEM;
}
init_completion(&dev->cmd_complete);
#ifdef CONFIG_CPU_FREQ
init_completion(&dev->xfr_complete);
#endif
- dev->dev = get_device(&pdev->dev);
+ dev->dev = &pdev->dev;
dev->irq = irq->start;
dev->pdata = dev->dev->platform_data;
platform_set_drvdata(pdev, dev);
@@ -686,10 +680,9 @@ static int davinci_i2c_probe(struct platform_device *pdev)
dev->pdata = devm_kzalloc(&pdev->dev,
sizeof(struct davinci_i2c_platform_data), GFP_KERNEL);
- if (!dev->pdata) {
- r = -ENOMEM;
- goto err_free_mem;
- }
+ if (!dev->pdata)
+ return -ENOMEM;
+
memcpy(dev->pdata, &davinci_i2c_platform_data_default,
sizeof(struct davinci_i2c_platform_data));
if (!of_property_read_u32(pdev->dev.of_node, "clock-frequency",
@@ -699,22 +692,21 @@ static int davinci_i2c_probe(struct platform_device *pdev)
dev->pdata = &davinci_i2c_platform_data_default;
}
- dev->clk = clk_get(&pdev->dev, NULL);
- if (IS_ERR(dev->clk)) {
- r = -ENODEV;
- goto err_free_mem;
- }
+ dev->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(dev->clk))
+ return -ENODEV;
clk_prepare_enable(dev->clk);
- dev->base = ioremap(mem->start, resource_size(mem));
- if (!dev->base) {
- r = -EBUSY;
- goto err_mem_ioremap;
+ dev->base = devm_ioremap_resource(&pdev->dev, mem);
+ if (IS_ERR(dev->base)) {
+ r = PTR_ERR(dev->base);
+ goto err_unuse_clocks;
}
i2c_davinci_init(dev);
- r = request_irq(dev->irq, i2c_davinci_isr, 0, pdev->name, dev);
+ r = devm_request_irq(&pdev->dev, dev->irq, i2c_davinci_isr, 0,
+ pdev->name, dev);
if (r) {
dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
goto err_unuse_clocks;
@@ -723,7 +715,7 @@ static int davinci_i2c_probe(struct platform_device *pdev)
r = i2c_davinci_cpufreq_register(dev);
if (r) {
dev_err(&pdev->dev, "failed to register cpufreq\n");
- goto err_free_irq;
+ goto err_unuse_clocks;
}
adap = &dev->adapter;
@@ -740,50 +732,31 @@ static int davinci_i2c_probe(struct platform_device *pdev)
r = i2c_add_numbered_adapter(adap);
if (r) {
dev_err(&pdev->dev, "failure adding adapter\n");
- goto err_free_irq;
+ goto err_unuse_clocks;
}
of_i2c_register_devices(adap);
return 0;
-err_free_irq:
- free_irq(dev->irq, dev);
err_unuse_clocks:
- iounmap(dev->base);
-err_mem_ioremap:
clk_disable_unprepare(dev->clk);
- clk_put(dev->clk);
dev->clk = NULL;
-err_free_mem:
- put_device(&pdev->dev);
- kfree(dev);
-err_release_region:
- release_mem_region(mem->start, resource_size(mem));
-
return r;
}
static int davinci_i2c_remove(struct platform_device *pdev)
{
struct davinci_i2c_dev *dev = platform_get_drvdata(pdev);
- struct resource *mem;
i2c_davinci_cpufreq_deregister(dev);
i2c_del_adapter(&dev->adapter);
- put_device(&pdev->dev);
clk_disable_unprepare(dev->clk);
- clk_put(dev->clk);
dev->clk = NULL;
davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, 0);
- free_irq(dev->irq, dev);
- iounmap(dev->base);
- kfree(dev);
- mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- release_mem_region(mem->start, resource_size(mem));
return 0;
}
diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c
index 94fd81875409..21fbb340ad66 100644
--- a/drivers/i2c/busses/i2c-designware-core.c
+++ b/drivers/i2c/busses/i2c-designware-core.c
@@ -68,6 +68,7 @@
#define DW_IC_TXFLR 0x74
#define DW_IC_RXFLR 0x78
#define DW_IC_TX_ABRT_SOURCE 0x80
+#define DW_IC_ENABLE_STATUS 0x9c
#define DW_IC_COMP_PARAM_1 0xf4
#define DW_IC_COMP_TYPE 0xfc
#define DW_IC_COMP_TYPE_VALUE 0x44570140
@@ -248,6 +249,27 @@ static u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset)
return ((ic_clk * (tLOW + tf) + 5000) / 10000) - 1 + offset;
}
+static void __i2c_dw_enable(struct dw_i2c_dev *dev, bool enable)
+{
+ int timeout = 100;
+
+ do {
+ dw_writel(dev, enable, DW_IC_ENABLE);
+ if ((dw_readl(dev, DW_IC_ENABLE_STATUS) & 1) == enable)
+ return;
+
+ /*
+ * Wait 10 times the signaling period of the highest I2C
+ * transfer supported by the driver (for 400KHz this is
+ * 25us) as described in the DesignWare I2C databook.
+ */
+ usleep_range(25, 250);
+ } while (timeout--);
+
+ dev_warn(dev->dev, "timeout in %sabling adapter\n",
+ enable ? "en" : "dis");
+}
+
/**
* i2c_dw_init() - initialize the designware i2c master hardware
* @dev: device private data
@@ -278,7 +300,7 @@ int i2c_dw_init(struct dw_i2c_dev *dev)
}
/* Disable the adapter */
- dw_writel(dev, 0, DW_IC_ENABLE);
+ __i2c_dw_enable(dev, false);
/* set standard and fast speed deviders for high/low periods */
@@ -333,7 +355,7 @@ static int i2c_dw_wait_bus_not_busy(struct dw_i2c_dev *dev)
return -ETIMEDOUT;
}
timeout--;
- mdelay(1);
+ usleep_range(1000, 1100);
}
return 0;
@@ -345,7 +367,7 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
u32 ic_con;
/* Disable the adapter */
- dw_writel(dev, 0, DW_IC_ENABLE);
+ __i2c_dw_enable(dev, false);
/* set the slave (target) address */
dw_writel(dev, msgs[dev->msg_write_idx].addr, DW_IC_TAR);
@@ -359,7 +381,7 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
dw_writel(dev, ic_con, DW_IC_CON);
/* Enable the adapter */
- dw_writel(dev, 1, DW_IC_ENABLE);
+ __i2c_dw_enable(dev, true);
/* Enable interrupts */
dw_writel(dev, DW_IC_INTR_DEFAULT_MASK, DW_IC_INTR_MASK);
@@ -565,7 +587,7 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
/* no error */
if (likely(!dev->cmd_err)) {
/* Disable the adapter */
- dw_writel(dev, 0, DW_IC_ENABLE);
+ __i2c_dw_enable(dev, false);
ret = num;
goto done;
}
@@ -578,7 +600,8 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
ret = -EIO;
done:
- pm_runtime_put(dev->dev);
+ pm_runtime_mark_last_busy(dev->dev);
+ pm_runtime_put_autosuspend(dev->dev);
mutex_unlock(&dev->lock);
return ret;
@@ -700,7 +723,7 @@ EXPORT_SYMBOL_GPL(i2c_dw_isr);
void i2c_dw_enable(struct dw_i2c_dev *dev)
{
/* Enable the adapter */
- dw_writel(dev, 1, DW_IC_ENABLE);
+ __i2c_dw_enable(dev, true);
}
EXPORT_SYMBOL_GPL(i2c_dw_enable);
@@ -713,7 +736,7 @@ EXPORT_SYMBOL_GPL(i2c_dw_is_enabled);
void i2c_dw_disable(struct dw_i2c_dev *dev)
{
/* Disable controller */
- dw_writel(dev, 0, DW_IC_ENABLE);
+ __i2c_dw_enable(dev, false);
/* Disable all interupts */
dw_writel(dev, 0, DW_IC_INTR_MASK);
diff --git a/drivers/i2c/busses/i2c-designware-pcidrv.c b/drivers/i2c/busses/i2c-designware-pcidrv.c
index 7c5e383c350d..f6ed06c966ee 100644
--- a/drivers/i2c/busses/i2c-designware-pcidrv.c
+++ b/drivers/i2c/busses/i2c-designware-pcidrv.c
@@ -208,68 +208,45 @@ static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
}
static int i2c_dw_pci_probe(struct pci_dev *pdev,
-const struct pci_device_id *id)
+ const struct pci_device_id *id)
{
struct dw_i2c_dev *dev;
struct i2c_adapter *adap;
- unsigned long start, len;
- void __iomem *base;
int r;
struct dw_pci_controller *controller;
if (id->driver_data >= ARRAY_SIZE(dw_pci_controllers)) {
- printk(KERN_ERR "dw_i2c_pci_probe: invalid driver data %ld\n",
+ dev_err(&pdev->dev, "%s: invalid driver data %ld\n", __func__,
id->driver_data);
return -EINVAL;
}
controller = &dw_pci_controllers[id->driver_data];
- r = pci_enable_device(pdev);
+ r = pcim_enable_device(pdev);
if (r) {
dev_err(&pdev->dev, "Failed to enable I2C PCI device (%d)\n",
r);
- goto exit;
+ return r;
}
- /* Determine the address of the I2C area */
- start = pci_resource_start(pdev, 0);
- len = pci_resource_len(pdev, 0);
- if (!start || len == 0) {
- dev_err(&pdev->dev, "base address not set\n");
- r = -ENODEV;
- goto exit;
- }
-
- r = pci_request_region(pdev, 0, DRIVER_NAME);
+ r = pcim_iomap_regions(pdev, 1 << 0, pci_name(pdev));
if (r) {
- dev_err(&pdev->dev, "failed to request I2C region "
- "0x%lx-0x%lx\n", start,
- (unsigned long)pci_resource_end(pdev, 0));
- goto exit;
- }
-
- base = ioremap_nocache(start, len);
- if (!base) {
dev_err(&pdev->dev, "I/O memory remapping failed\n");
- r = -ENOMEM;
- goto err_release_region;
+ return r;
}
-
- dev = kzalloc(sizeof(struct dw_i2c_dev), GFP_KERNEL);
- if (!dev) {
- r = -ENOMEM;
- goto err_release_region;
- }
+ dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
+ if (!dev)
+ return -ENOMEM;
init_completion(&dev->cmd_complete);
mutex_init(&dev->lock);
dev->clk = NULL;
dev->controller = controller;
dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
- dev->base = base;
- dev->dev = get_device(&pdev->dev);
+ dev->base = pcim_iomap_table(pdev)[0];
+ dev->dev = &pdev->dev;
dev->functionality =
I2C_FUNC_I2C |
I2C_FUNC_SMBUS_BYTE |
@@ -284,7 +261,7 @@ const struct pci_device_id *id)
dev->rx_fifo_depth = controller->rx_fifo_depth;
r = i2c_dw_init(dev);
if (r)
- goto err_iounmap;
+ return r;
adap = &dev->adapter;
i2c_set_adapdata(adap, dev);
@@ -296,10 +273,11 @@ const struct pci_device_id *id)
snprintf(adap->name, sizeof(adap->name), "i2c-designware-pci-%d",
adap->nr);
- r = request_irq(pdev->irq, i2c_dw_isr, IRQF_SHARED, adap->name, dev);
+ r = devm_request_irq(&pdev->dev, pdev->irq, i2c_dw_isr, IRQF_SHARED,
+ adap->name, dev);
if (r) {
dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
- goto err_iounmap;
+ return r;
}
i2c_dw_disable_int(dev);
@@ -307,24 +285,14 @@ const struct pci_device_id *id)
r = i2c_add_numbered_adapter(adap);
if (r) {
dev_err(&pdev->dev, "failure adding adapter\n");
- goto err_free_irq;
+ return r;
}
- pm_runtime_put_noidle(&pdev->dev);
+ pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
+ pm_runtime_use_autosuspend(&pdev->dev);
pm_runtime_allow(&pdev->dev);
return 0;
-
-err_free_irq:
- free_irq(pdev->irq, dev);
-err_iounmap:
- iounmap(dev->base);
- put_device(&pdev->dev);
- kfree(dev);
-err_release_region:
- pci_release_region(pdev, 0);
-exit:
- return r;
}
static void i2c_dw_pci_remove(struct pci_dev *pdev)
@@ -336,11 +304,6 @@ static void i2c_dw_pci_remove(struct pci_dev *pdev)
pm_runtime_get_noresume(&pdev->dev);
i2c_del_adapter(&dev->adapter);
- put_device(&pdev->dev);
-
- free_irq(dev->irq, dev);
- kfree(dev);
- pci_release_region(pdev, 0);
}
/* work with hotplug and coldplug */
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index e3085c487ace..8ec91335d95a 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -56,20 +56,11 @@ static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
static int dw_i2c_acpi_configure(struct platform_device *pdev)
{
struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
- struct acpi_device *adev;
- int busno, ret;
if (!ACPI_HANDLE(&pdev->dev))
return -ENODEV;
- ret = acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev);
- if (ret)
- return -ENODEV;
-
dev->adapter.nr = -1;
- if (adev->pnp.unique_id && !kstrtoint(adev->pnp.unique_id, 0, &busno))
- dev->adapter.nr = busno;
-
dev->tx_fifo_depth = 32;
dev->rx_fifo_depth = 32;
return 0;
@@ -92,7 +83,7 @@ static int dw_i2c_probe(struct platform_device *pdev)
{
struct dw_i2c_dev *dev;
struct i2c_adapter *adap;
- struct resource *mem, *ioarea;
+ struct resource *mem;
int irq, r;
/* NOTE: driver uses the static register mapping */
@@ -108,32 +99,25 @@ static int dw_i2c_probe(struct platform_device *pdev)
return irq; /* -ENXIO */
}
- ioarea = request_mem_region(mem->start, resource_size(mem),
- pdev->name);
- if (!ioarea) {
- dev_err(&pdev->dev, "I2C region already claimed\n");
- return -EBUSY;
- }
+ dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
+ if (!dev)
+ return -ENOMEM;
- dev = kzalloc(sizeof(struct dw_i2c_dev), GFP_KERNEL);
- if (!dev) {
- r = -ENOMEM;
- goto err_release_region;
- }
+ dev->base = devm_ioremap_resource(&pdev->dev, mem);
+ if (IS_ERR(dev->base))
+ return PTR_ERR(dev->base);
init_completion(&dev->cmd_complete);
mutex_init(&dev->lock);
- dev->dev = get_device(&pdev->dev);
+ dev->dev = &pdev->dev;
dev->irq = irq;
platform_set_drvdata(pdev, dev);
- dev->clk = clk_get(&pdev->dev, NULL);
+ dev->clk = devm_clk_get(&pdev->dev, NULL);
dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
- if (IS_ERR(dev->clk)) {
- r = -ENODEV;
- goto err_free_mem;
- }
+ if (IS_ERR(dev->clk))
+ return PTR_ERR(dev->clk);
clk_prepare_enable(dev->clk);
dev->functionality =
@@ -146,13 +130,6 @@ static int dw_i2c_probe(struct platform_device *pdev)
dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST;
- dev->base = ioremap(mem->start, resource_size(mem));
- if (dev->base == NULL) {
- dev_err(&pdev->dev, "failure mapping io resources\n");
- r = -EBUSY;
- goto err_unuse_clocks;
- }
-
/* Try first if we can configure the device from ACPI */
r = dw_i2c_acpi_configure(pdev);
if (r) {
@@ -164,13 +141,14 @@ static int dw_i2c_probe(struct platform_device *pdev)
}
r = i2c_dw_init(dev);
if (r)
- goto err_iounmap;
+ return r;
i2c_dw_disable_int(dev);
- r = request_irq(dev->irq, i2c_dw_isr, IRQF_SHARED, pdev->name, dev);
+ r = devm_request_irq(&pdev->dev, dev->irq, i2c_dw_isr, IRQF_SHARED,
+ pdev->name, dev);
if (r) {
dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
- goto err_iounmap;
+ return r;
}
adap = &dev->adapter;
@@ -186,57 +164,32 @@ static int dw_i2c_probe(struct platform_device *pdev)
r = i2c_add_numbered_adapter(adap);
if (r) {
dev_err(&pdev->dev, "failure adding adapter\n");
- goto err_free_irq;
+ return r;
}
of_i2c_register_devices(adap);
acpi_i2c_register_devices(adap);
+ pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
+ pm_runtime_use_autosuspend(&pdev->dev);
pm_runtime_set_active(&pdev->dev);
pm_runtime_enable(&pdev->dev);
- pm_runtime_put(&pdev->dev);
return 0;
-
-err_free_irq:
- free_irq(dev->irq, dev);
-err_iounmap:
- iounmap(dev->base);
-err_unuse_clocks:
- clk_disable_unprepare(dev->clk);
- clk_put(dev->clk);
- dev->clk = NULL;
-err_free_mem:
- put_device(&pdev->dev);
- kfree(dev);
-err_release_region:
- release_mem_region(mem->start, resource_size(mem));
-
- return r;
}
static int dw_i2c_remove(struct platform_device *pdev)
{
struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
- struct resource *mem;
pm_runtime_get_sync(&pdev->dev);
i2c_del_adapter(&dev->adapter);
- put_device(&pdev->dev);
-
- clk_disable_unprepare(dev->clk);
- clk_put(dev->clk);
- dev->clk = NULL;
i2c_dw_disable(dev);
- free_irq(dev->irq, dev);
- kfree(dev);
pm_runtime_put(&pdev->dev);
pm_runtime_disable(&pdev->dev);
- mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- release_mem_region(mem->start, resource_size(mem));
return 0;
}
diff --git a/drivers/i2c/busses/i2c-gpio.c b/drivers/i2c/busses/i2c-gpio.c
index f3fa4332bbdf..bc6e139c6e7f 100644
--- a/drivers/i2c/busses/i2c-gpio.c
+++ b/drivers/i2c/busses/i2c-gpio.c
@@ -85,23 +85,29 @@ static int i2c_gpio_getscl(void *data)
return gpio_get_value(pdata->scl_pin);
}
-static int of_i2c_gpio_probe(struct device_node *np,
- struct i2c_gpio_platform_data *pdata)
+static int of_i2c_gpio_get_pins(struct device_node *np,
+ unsigned int *sda_pin, unsigned int *scl_pin)
{
- u32 reg;
-
if (of_gpio_count(np) < 2)
return -ENODEV;
- pdata->sda_pin = of_get_gpio(np, 0);
- pdata->scl_pin = of_get_gpio(np, 1);
+ *sda_pin = of_get_gpio(np, 0);
+ *scl_pin = of_get_gpio(np, 1);
- if (!gpio_is_valid(pdata->sda_pin) || !gpio_is_valid(pdata->scl_pin)) {
+ if (!gpio_is_valid(*sda_pin) || !gpio_is_valid(*scl_pin)) {
pr_err("%s: invalid GPIO pins, sda=%d/scl=%d\n",
- np->full_name, pdata->sda_pin, pdata->scl_pin);
+ np->full_name, *sda_pin, *scl_pin);
return -ENODEV;
}
+ return 0;
+}
+
+static void of_i2c_gpio_get_props(struct device_node *np,
+ struct i2c_gpio_platform_data *pdata)
+{
+ u32 reg;
+
of_property_read_u32(np, "i2c-gpio,delay-us", &pdata->udelay);
if (!of_property_read_u32(np, "i2c-gpio,timeout-ms", &reg))
@@ -113,8 +119,6 @@ static int of_i2c_gpio_probe(struct device_node *np,
of_property_read_bool(np, "i2c-gpio,scl-open-drain");
pdata->scl_is_output_only =
of_property_read_bool(np, "i2c-gpio,scl-output-only");
-
- return 0;
}
static int i2c_gpio_probe(struct platform_device *pdev)
@@ -123,31 +127,52 @@ static int i2c_gpio_probe(struct platform_device *pdev)
struct i2c_gpio_platform_data *pdata;
struct i2c_algo_bit_data *bit_data;
struct i2c_adapter *adap;
+ unsigned int sda_pin, scl_pin;
int ret;
- priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
- if (!priv)
- return -ENOMEM;
- adap = &priv->adap;
- bit_data = &priv->bit_data;
- pdata = &priv->pdata;
-
+ /* First get the GPIO pins; if it fails, we'll defer the probe. */
if (pdev->dev.of_node) {
- ret = of_i2c_gpio_probe(pdev->dev.of_node, pdata);
+ ret = of_i2c_gpio_get_pins(pdev->dev.of_node,
+ &sda_pin, &scl_pin);
if (ret)
return ret;
} else {
if (!pdev->dev.platform_data)
return -ENXIO;
- memcpy(pdata, pdev->dev.platform_data, sizeof(*pdata));
+ pdata = pdev->dev.platform_data;
+ sda_pin = pdata->sda_pin;
+ scl_pin = pdata->scl_pin;
}
- ret = gpio_request(pdata->sda_pin, "sda");
- if (ret)
+ ret = gpio_request(sda_pin, "sda");
+ if (ret) {
+ if (ret == -EINVAL)
+ ret = -EPROBE_DEFER; /* Try again later */
goto err_request_sda;
- ret = gpio_request(pdata->scl_pin, "scl");
- if (ret)
+ }
+ ret = gpio_request(scl_pin, "scl");
+ if (ret) {
+ if (ret == -EINVAL)
+ ret = -EPROBE_DEFER; /* Try again later */
goto err_request_scl;
+ }
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv) {
+ ret = -ENOMEM;
+ goto err_add_bus;
+ }
+ adap = &priv->adap;
+ bit_data = &priv->bit_data;
+ pdata = &priv->pdata;
+
+ if (pdev->dev.of_node) {
+ pdata->sda_pin = sda_pin;
+ pdata->scl_pin = scl_pin;
+ of_i2c_gpio_get_props(pdev->dev.of_node, pdata);
+ } else {
+ memcpy(pdata, pdev->dev.platform_data, sizeof(*pdata));
+ }
if (pdata->sda_is_open_drain) {
gpio_direction_output(pdata->sda_pin, 1);
@@ -211,9 +236,9 @@ static int i2c_gpio_probe(struct platform_device *pdev)
return 0;
err_add_bus:
- gpio_free(pdata->scl_pin);
+ gpio_free(scl_pin);
err_request_scl:
- gpio_free(pdata->sda_pin);
+ gpio_free(sda_pin);
err_request_sda:
return ret;
}
diff --git a/drivers/i2c/busses/i2c-intel-mid.c b/drivers/i2c/busses/i2c-intel-mid.c
index 323fa018ffd5..0fb659726ffc 100644
--- a/drivers/i2c/busses/i2c-intel-mid.c
+++ b/drivers/i2c/busses/i2c-intel-mid.c
@@ -1082,8 +1082,7 @@ static void intel_mid_i2c_remove(struct pci_dev *dev)
{
struct intel_mid_i2c_private *mrst = pci_get_drvdata(dev);
intel_mid_i2c_disable(&mrst->adap);
- if (i2c_del_adapter(&mrst->adap))
- dev_err(&dev->dev, "Failed to delete i2c adapter");
+ i2c_del_adapter(&mrst->adap);
free_irq(dev->irq, mrst);
iounmap(mrst->base);
diff --git a/drivers/i2c/busses/i2c-ismt.c b/drivers/i2c/busses/i2c-ismt.c
index 130f02cc9d94..cd82eb44e4c4 100644
--- a/drivers/i2c/busses/i2c-ismt.c
+++ b/drivers/i2c/busses/i2c-ismt.c
@@ -183,7 +183,7 @@ struct ismt_priv {
/**
* ismt_ids - PCI device IDs supported by this driver
*/
-static const DEFINE_PCI_DEVICE_TABLE(ismt_ids) = {
+static DEFINE_PCI_DEVICE_TABLE(ismt_ids) = {
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_S1200_SMT0) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_S1200_SMT1) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_AVOTON_SMT) },
diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c
index 8b20ef8524ac..3bbd65d35a5e 100644
--- a/drivers/i2c/busses/i2c-mv64xxx.c
+++ b/drivers/i2c/busses/i2c-mv64xxx.c
@@ -701,9 +701,8 @@ static int
mv64xxx_i2c_remove(struct platform_device *dev)
{
struct mv64xxx_i2c_data *drv_data = platform_get_drvdata(dev);
- int rc;
- rc = i2c_del_adapter(&drv_data->adapter);
+ i2c_del_adapter(&drv_data->adapter);
free_irq(drv_data->irq, drv_data);
mv64xxx_i2c_unmap_regs(drv_data);
#if defined(CONFIG_HAVE_CLK)
@@ -715,7 +714,7 @@ mv64xxx_i2c_remove(struct platform_device *dev)
#endif
kfree(drv_data);
- return rc;
+ return 0;
}
static const struct of_device_id mv64xxx_i2c_of_match_table[] = {
diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.c
index 120f24646696..c67d89fc6254 100644
--- a/drivers/i2c/busses/i2c-mxs.c
+++ b/drivers/i2c/busses/i2c-mxs.c
@@ -56,6 +56,7 @@
#define MXS_I2C_CTRL1_SET (0x44)
#define MXS_I2C_CTRL1_CLR (0x48)
+#define MXS_I2C_CTRL1_CLR_GOT_A_NAK 0x10000000
#define MXS_I2C_CTRL1_BUS_FREE_IRQ 0x80
#define MXS_I2C_CTRL1_DATA_ENGINE_CMPLT_IRQ 0x40
#define MXS_I2C_CTRL1_NO_SLAVE_ACK_IRQ 0x20
@@ -65,6 +66,10 @@
#define MXS_I2C_CTRL1_SLAVE_STOP_IRQ 0x02
#define MXS_I2C_CTRL1_SLAVE_IRQ 0x01
+#define MXS_I2C_STAT (0x50)
+#define MXS_I2C_STAT_BUS_BUSY 0x00000800
+#define MXS_I2C_STAT_CLK_GEN_BUSY 0x00000400
+
#define MXS_I2C_DATA (0xa0)
#define MXS_I2C_DEBUG0 (0xb0)
@@ -297,12 +302,10 @@ static int mxs_i2c_pio_wait_dmareq(struct mxs_i2c_dev *i2c)
cond_resched();
}
- writel(MXS_I2C_DEBUG0_DMAREQ, i2c->regs + MXS_I2C_DEBUG0_CLR);
-
return 0;
}
-static int mxs_i2c_pio_wait_cplt(struct mxs_i2c_dev *i2c)
+static int mxs_i2c_pio_wait_cplt(struct mxs_i2c_dev *i2c, int last)
{
unsigned long timeout = jiffies + msecs_to_jiffies(1000);
@@ -323,9 +326,50 @@ static int mxs_i2c_pio_wait_cplt(struct mxs_i2c_dev *i2c)
writel(MXS_I2C_CTRL1_DATA_ENGINE_CMPLT_IRQ,
i2c->regs + MXS_I2C_CTRL1_CLR);
+ /*
+ * When ending a transfer with a stop, we have to wait for the bus to
+ * go idle before we report the transfer as completed. Otherwise the
+ * start of the next transfer may race with the end of the current one.
+ */
+ while (last && (readl(i2c->regs + MXS_I2C_STAT) &
+ (MXS_I2C_STAT_BUS_BUSY | MXS_I2C_STAT_CLK_GEN_BUSY))) {
+ if (time_after(jiffies, timeout))
+ return -ETIMEDOUT;
+ cond_resched();
+ }
+
return 0;
}
+static int mxs_i2c_pio_check_error_state(struct mxs_i2c_dev *i2c)
+{
+ u32 state;
+
+ state = readl(i2c->regs + MXS_I2C_CTRL1_CLR) & MXS_I2C_IRQ_MASK;
+
+ if (state & MXS_I2C_CTRL1_NO_SLAVE_ACK_IRQ)
+ i2c->cmd_err = -ENXIO;
+ else if (state & (MXS_I2C_CTRL1_EARLY_TERM_IRQ |
+ MXS_I2C_CTRL1_MASTER_LOSS_IRQ |
+ MXS_I2C_CTRL1_SLAVE_STOP_IRQ |
+ MXS_I2C_CTRL1_SLAVE_IRQ))
+ i2c->cmd_err = -EIO;
+
+ return i2c->cmd_err;
+}
+
+static void mxs_i2c_pio_trigger_cmd(struct mxs_i2c_dev *i2c, u32 cmd)
+{
+ u32 reg;
+
+ writel(cmd, i2c->regs + MXS_I2C_CTRL0);
+
+ /* readback makes sure the write is latched into hardware */
+ reg = readl(i2c->regs + MXS_I2C_CTRL0);
+ reg |= MXS_I2C_CTRL0_RUN;
+ writel(reg, i2c->regs + MXS_I2C_CTRL0);
+}
+
static int mxs_i2c_pio_setup_xfer(struct i2c_adapter *adap,
struct i2c_msg *msg, uint32_t flags)
{
@@ -341,23 +385,26 @@ static int mxs_i2c_pio_setup_xfer(struct i2c_adapter *adap,
addr_data |= I2C_SMBUS_READ;
/* SELECT command. */
- writel(MXS_I2C_CTRL0_RUN | MXS_CMD_I2C_SELECT,
- i2c->regs + MXS_I2C_CTRL0);
+ mxs_i2c_pio_trigger_cmd(i2c, MXS_CMD_I2C_SELECT);
ret = mxs_i2c_pio_wait_dmareq(i2c);
if (ret)
return ret;
writel(addr_data, i2c->regs + MXS_I2C_DATA);
+ writel(MXS_I2C_DEBUG0_DMAREQ, i2c->regs + MXS_I2C_DEBUG0_CLR);
- ret = mxs_i2c_pio_wait_cplt(i2c);
+ ret = mxs_i2c_pio_wait_cplt(i2c, 0);
if (ret)
return ret;
+ if (mxs_i2c_pio_check_error_state(i2c))
+ goto cleanup;
+
/* READ command. */
- writel(MXS_I2C_CTRL0_RUN | MXS_CMD_I2C_READ | flags |
- MXS_I2C_CTRL0_XFER_COUNT(msg->len),
- i2c->regs + MXS_I2C_CTRL0);
+ mxs_i2c_pio_trigger_cmd(i2c,
+ MXS_CMD_I2C_READ | flags |
+ MXS_I2C_CTRL0_XFER_COUNT(msg->len));
for (i = 0; i < msg->len; i++) {
if ((i & 3) == 0) {
@@ -365,6 +412,8 @@ static int mxs_i2c_pio_setup_xfer(struct i2c_adapter *adap,
if (ret)
return ret;
data = readl(i2c->regs + MXS_I2C_DATA);
+ writel(MXS_I2C_DEBUG0_DMAREQ,
+ i2c->regs + MXS_I2C_DEBUG0_CLR);
}
msg->buf[i] = data & 0xff;
data >>= 8;
@@ -373,9 +422,9 @@ static int mxs_i2c_pio_setup_xfer(struct i2c_adapter *adap,
addr_data |= I2C_SMBUS_WRITE;
/* WRITE command. */
- writel(MXS_I2C_CTRL0_RUN | MXS_CMD_I2C_WRITE | flags |
- MXS_I2C_CTRL0_XFER_COUNT(msg->len + 1),
- i2c->regs + MXS_I2C_CTRL0);
+ mxs_i2c_pio_trigger_cmd(i2c,
+ MXS_CMD_I2C_WRITE | flags |
+ MXS_I2C_CTRL0_XFER_COUNT(msg->len + 1));
/*
* The LSB of data buffer is the first byte blasted across
@@ -391,6 +440,8 @@ static int mxs_i2c_pio_setup_xfer(struct i2c_adapter *adap,
if (ret)
return ret;
writel(data, i2c->regs + MXS_I2C_DATA);
+ writel(MXS_I2C_DEBUG0_DMAREQ,
+ i2c->regs + MXS_I2C_DEBUG0_CLR);
}
}
@@ -401,13 +452,19 @@ static int mxs_i2c_pio_setup_xfer(struct i2c_adapter *adap,
if (ret)
return ret;
writel(data, i2c->regs + MXS_I2C_DATA);
+ writel(MXS_I2C_DEBUG0_DMAREQ,
+ i2c->regs + MXS_I2C_DEBUG0_CLR);
}
}
- ret = mxs_i2c_pio_wait_cplt(i2c);
+ ret = mxs_i2c_pio_wait_cplt(i2c, flags & MXS_I2C_CTRL0_POST_SEND_STOP);
if (ret)
return ret;
+ /* make sure we capture any occurred error into cmd_err */
+ mxs_i2c_pio_check_error_state(i2c);
+
+cleanup:
/* Clear any dangling IRQs and re-enable interrupts. */
writel(MXS_I2C_IRQ_MASK, i2c->regs + MXS_I2C_CTRL1_CLR);
writel(MXS_I2C_IRQ_MASK << 8, i2c->regs + MXS_I2C_CTRL1_SET);
@@ -439,12 +496,12 @@ static int mxs_i2c_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg,
* using PIO mode while longer transfers use DMA. The 8 byte border is
* based on this empirical measurement and a lot of previous frobbing.
*/
+ i2c->cmd_err = 0;
if (msg->len < 8) {
ret = mxs_i2c_pio_setup_xfer(adap, msg, flags);
if (ret)
mxs_i2c_reset(i2c);
} else {
- i2c->cmd_err = 0;
INIT_COMPLETION(i2c->cmd_complete);
ret = mxs_i2c_dma_setup_xfer(adap, msg, flags);
if (ret)
@@ -454,13 +511,19 @@ static int mxs_i2c_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg,
msecs_to_jiffies(1000));
if (ret == 0)
goto timeout;
+ }
- if (i2c->cmd_err == -ENXIO)
- mxs_i2c_reset(i2c);
-
- ret = i2c->cmd_err;
+ if (i2c->cmd_err == -ENXIO) {
+ /*
+ * If the transfer fails with a NAK from the slave the
+ * controller halts until it gets told to return to idle state.
+ */
+ writel(MXS_I2C_CTRL1_CLR_GOT_A_NAK,
+ i2c->regs + MXS_I2C_CTRL1_SET);
}
+ ret = i2c->cmd_err;
+
dev_dbg(i2c->dev, "Done with err=%d\n", ret);
return ret;
@@ -686,11 +749,8 @@ static int mxs_i2c_probe(struct platform_device *pdev)
static int mxs_i2c_remove(struct platform_device *pdev)
{
struct mxs_i2c_dev *i2c = platform_get_drvdata(pdev);
- int ret;
- ret = i2c_del_adapter(&i2c->adapter);
- if (ret)
- return -EBUSY;
+ i2c_del_adapter(&i2c->adapter);
if (i2c->dmach)
dma_release_channel(i2c->dmach);
diff --git a/drivers/i2c/busses/i2c-nforce2-s4985.c b/drivers/i2c/busses/i2c-nforce2-s4985.c
index 29015eb9ca46..2ca268d6140b 100644
--- a/drivers/i2c/busses/i2c-nforce2-s4985.c
+++ b/drivers/i2c/busses/i2c-nforce2-s4985.c
@@ -164,11 +164,7 @@ static int __init nforce2_s4985_init(void)
}
/* Unregister physical bus */
- error = i2c_del_adapter(nforce2_smbus);
- if (error) {
- dev_err(&nforce2_smbus->dev, "Physical bus removal failed\n");
- goto ERROR0;
- }
+ i2c_del_adapter(nforce2_smbus);
printk(KERN_INFO "Enabling SMBus multiplexing for Tyan S4985\n");
/* Define the 5 virtual adapters and algorithms structures */
diff --git a/drivers/i2c/busses/i2c-octeon.c b/drivers/i2c/busses/i2c-octeon.c
index 935585ef4d39..956fe320f313 100644
--- a/drivers/i2c/busses/i2c-octeon.c
+++ b/drivers/i2c/busses/i2c-octeon.c
@@ -183,7 +183,7 @@ static irqreturn_t octeon_i2c_isr(int irq, void *dev_id)
struct octeon_i2c *i2c = dev_id;
octeon_i2c_int_disable(i2c);
- wake_up_interruptible(&i2c->queue);
+ wake_up(&i2c->queue);
return IRQ_HANDLED;
}
@@ -206,9 +206,9 @@ static int octeon_i2c_wait(struct octeon_i2c *i2c)
octeon_i2c_int_enable(i2c);
- result = wait_event_interruptible_timeout(i2c->queue,
- octeon_i2c_test_iflg(i2c),
- i2c->adap.timeout);
+ result = wait_event_timeout(i2c->queue,
+ octeon_i2c_test_iflg(i2c),
+ i2c->adap.timeout);
octeon_i2c_int_disable(i2c);
@@ -440,7 +440,7 @@ static struct i2c_adapter octeon_i2c_ops = {
.owner = THIS_MODULE,
.name = "OCTEON adapter",
.algo = &octeon_i2c_algo,
- .timeout = 2,
+ .timeout = HZ / 50,
};
/**
diff --git a/drivers/i2c/busses/i2c-powermac.c b/drivers/i2c/busses/i2c-powermac.c
index da54e673449d..8dc90da1e6e6 100644
--- a/drivers/i2c/busses/i2c-powermac.c
+++ b/drivers/i2c/busses/i2c-powermac.c
@@ -213,14 +213,8 @@ static const struct i2c_algorithm i2c_powermac_algorithm = {
static int i2c_powermac_remove(struct platform_device *dev)
{
struct i2c_adapter *adapter = platform_get_drvdata(dev);
- int rc;
-
- rc = i2c_del_adapter(adapter);
- /* We aren't that prepared to deal with this... */
- if (rc)
- printk(KERN_WARNING
- "i2c-powermac.c: Failed to remove bus %s !\n",
- adapter->name);
+
+ i2c_del_adapter(adapter);
memset(adapter, 0, sizeof(*adapter));
return 0;
diff --git a/drivers/i2c/busses/i2c-puv3.c b/drivers/i2c/busses/i2c-puv3.c
index 8acef657abf3..37a84c87c5fd 100644
--- a/drivers/i2c/busses/i2c-puv3.c
+++ b/drivers/i2c/busses/i2c-puv3.c
@@ -234,21 +234,15 @@ static int puv3_i2c_remove(struct platform_device *pdev)
{
struct i2c_adapter *adapter = platform_get_drvdata(pdev);
struct resource *mem;
- int rc;
- rc = i2c_del_adapter(adapter);
- if (rc) {
- dev_err(&pdev->dev, "Adapter '%s' delete fail\n",
- adapter->name);
- return rc;
- }
+ i2c_del_adapter(adapter);
put_device(&pdev->dev);
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
release_mem_region(mem->start, resource_size(mem));
- return rc;
+ return 0;
}
#ifdef CONFIG_PM
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index 1e88e8d66c55..ea6d45d1dcd6 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -1053,16 +1053,13 @@ static int i2c_pxa_probe_dt(struct platform_device *pdev, struct pxa_i2c *i2c,
struct device_node *np = pdev->dev.of_node;
const struct of_device_id *of_id =
of_match_device(i2c_pxa_dt_ids, &pdev->dev);
- int ret;
if (!of_id)
return 1;
- ret = of_alias_get_id(np, "i2c");
- if (ret < 0) {
- dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
- return ret;
- }
- pdev->id = ret;
+
+ /* For device tree we always use the dynamic or alias-assigned ID */
+ i2c->adap.nr = -1;
+
if (of_get_property(np, "mrvl,i2c-polling", NULL))
i2c->use_pio = 1;
if (of_get_property(np, "mrvl,i2c-fast-mode", NULL))
@@ -1100,6 +1097,9 @@ static int i2c_pxa_probe(struct platform_device *dev)
goto emalloc;
}
+ /* Default adapter num to device id; i2c_pxa_probe_dt can override. */
+ i2c->adap.nr = dev->id;
+
ret = i2c_pxa_probe_dt(dev, i2c, &i2c_type);
if (ret > 0)
ret = i2c_pxa_probe_pdata(dev, i2c, &i2c_type);
@@ -1124,9 +1124,7 @@ static int i2c_pxa_probe(struct platform_device *dev)
spin_lock_init(&i2c->lock);
init_waitqueue_head(&i2c->wait);
- i2c->adap.nr = dev->id;
- snprintf(i2c->adap.name, sizeof(i2c->adap.name), "pxa_i2c-i2c.%u",
- i2c->adap.nr);
+ strlcpy(i2c->adap.name, "pxa_i2c-i2c", sizeof(i2c->adap.name));
i2c->clk = clk_get(&dev->dev, NULL);
if (IS_ERR(i2c->clk)) {
@@ -1169,7 +1167,7 @@ static int i2c_pxa_probe(struct platform_device *dev)
} else {
i2c->adap.algo = &i2c_pxa_algorithm;
ret = request_irq(irq, i2c_pxa_handler, IRQF_SHARED,
- i2c->adap.name, i2c);
+ dev_name(&dev->dev), i2c);
if (ret)
goto ereqirq;
}
diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c
index f6b880ba1932..6e8ee92ab553 100644
--- a/drivers/i2c/busses/i2c-s3c2410.c
+++ b/drivers/i2c/busses/i2c-s3c2410.c
@@ -42,9 +42,46 @@
#include <asm/irq.h>
-#include <plat/regs-iic.h>
#include <linux/platform_data/i2c-s3c2410.h>
+/* see s3c2410x user guide, v1.1, section 9 (p447) for more info */
+
+#define S3C2410_IICCON 0x00
+#define S3C2410_IICSTAT 0x04
+#define S3C2410_IICADD 0x08
+#define S3C2410_IICDS 0x0C
+#define S3C2440_IICLC 0x10
+
+#define S3C2410_IICCON_ACKEN (1 << 7)
+#define S3C2410_IICCON_TXDIV_16 (0 << 6)
+#define S3C2410_IICCON_TXDIV_512 (1 << 6)
+#define S3C2410_IICCON_IRQEN (1 << 5)
+#define S3C2410_IICCON_IRQPEND (1 << 4)
+#define S3C2410_IICCON_SCALE(x) ((x) & 0xf)
+#define S3C2410_IICCON_SCALEMASK (0xf)
+
+#define S3C2410_IICSTAT_MASTER_RX (2 << 6)
+#define S3C2410_IICSTAT_MASTER_TX (3 << 6)
+#define S3C2410_IICSTAT_SLAVE_RX (0 << 6)
+#define S3C2410_IICSTAT_SLAVE_TX (1 << 6)
+#define S3C2410_IICSTAT_MODEMASK (3 << 6)
+
+#define S3C2410_IICSTAT_START (1 << 5)
+#define S3C2410_IICSTAT_BUSBUSY (1 << 5)
+#define S3C2410_IICSTAT_TXRXEN (1 << 4)
+#define S3C2410_IICSTAT_ARBITR (1 << 3)
+#define S3C2410_IICSTAT_ASSLAVE (1 << 2)
+#define S3C2410_IICSTAT_ADDR0 (1 << 1)
+#define S3C2410_IICSTAT_LASTBIT (1 << 0)
+
+#define S3C2410_IICLC_SDA_DELAY0 (0 << 0)
+#define S3C2410_IICLC_SDA_DELAY5 (1 << 0)
+#define S3C2410_IICLC_SDA_DELAY10 (2 << 0)
+#define S3C2410_IICLC_SDA_DELAY15 (3 << 0)
+#define S3C2410_IICLC_SDA_DELAY_MASK (3 << 0)
+
+#define S3C2410_IICLC_FILTER_ON (1 << 2)
+
/* Treat S3C2410 as baseline hardware, anything else is supported via quirks */
#define QUIRK_S3C2440 (1 << 0)
#define QUIRK_HDMIPHY (1 << 1)
@@ -309,6 +346,12 @@ static inline int is_lastmsg(struct s3c24xx_i2c *i2c)
static inline int is_msglast(struct s3c24xx_i2c *i2c)
{
+ /* msg->len is always 1 for the first byte of smbus block read.
+ * Actual length will be read from slave. More bytes will be
+ * read according to the length then. */
+ if (i2c->msg->flags & I2C_M_RECV_LEN && i2c->msg->len == 1)
+ return 0;
+
return i2c->msg_ptr == i2c->msg->len-1;
}
@@ -448,6 +491,9 @@ static int i2c_s3c_irq_nextbyte(struct s3c24xx_i2c *i2c, unsigned long iicstat)
byte = readb(i2c->regs + S3C2410_IICDS);
i2c->msg->buf[i2c->msg_ptr++] = byte;
+ /* Add actual length to read for smbus block read */
+ if (i2c->msg->flags & I2C_M_RECV_LEN && i2c->msg->len == 1)
+ i2c->msg->len += byte;
prepare_read:
if (is_msglast(i2c)) {
/* last byte of buffer */
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index b714776b6ddd..b60ff90adc39 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -25,7 +25,6 @@
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/slab.h>
-#include <linux/i2c-tegra.h>
#include <linux/of_i2c.h>
#include <linux/of_device.h>
#include <linux/module.h>
@@ -172,7 +171,7 @@ struct tegra_i2c_dev {
u8 *msg_buf;
size_t msg_buf_remaining;
int msg_read;
- unsigned long bus_clk_rate;
+ u32 bus_clk_rate;
bool is_suspended;
};
@@ -694,7 +693,6 @@ static const struct tegra_i2c_hw_feature tegra114_i2c_hw = {
.clk_divisor_std_fast_mode = 0x19,
};
-#if defined(CONFIG_OF)
/* Match table for of_platform binding */
static const struct of_device_id tegra_i2c_of_match[] = {
{ .compatible = "nvidia,tegra114-i2c", .data = &tegra114_i2c_hw, },
@@ -704,16 +702,13 @@ static const struct of_device_id tegra_i2c_of_match[] = {
{},
};
MODULE_DEVICE_TABLE(of, tegra_i2c_of_match);
-#endif
static int tegra_i2c_probe(struct platform_device *pdev)
{
struct tegra_i2c_dev *i2c_dev;
- struct tegra_i2c_platform_data *pdata = pdev->dev.platform_data;
struct resource *res;
struct clk *div_clk;
struct clk *fast_clk;
- const unsigned int *prop;
void __iomem *base;
int irq;
int ret = 0;
@@ -754,23 +749,16 @@ static int tegra_i2c_probe(struct platform_device *pdev)
i2c_dev->cont_id = pdev->id;
i2c_dev->dev = &pdev->dev;
- i2c_dev->bus_clk_rate = 100000; /* default clock rate */
- if (pdata) {
- i2c_dev->bus_clk_rate = pdata->bus_clk_rate;
-
- } else if (i2c_dev->dev->of_node) { /* if there is a device tree node ... */
- prop = of_get_property(i2c_dev->dev->of_node,
- "clock-frequency", NULL);
- if (prop)
- i2c_dev->bus_clk_rate = be32_to_cpup(prop);
- }
+ ret = of_property_read_u32(i2c_dev->dev->of_node, "clock-frequency",
+ &i2c_dev->bus_clk_rate);
+ if (ret)
+ i2c_dev->bus_clk_rate = 100000; /* default clock rate */
i2c_dev->hw = &tegra20_i2c_hw;
if (pdev->dev.of_node) {
const struct of_device_id *match;
- match = of_match_device(of_match_ptr(tegra_i2c_of_match),
- &pdev->dev);
+ match = of_match_device(tegra_i2c_of_match, &pdev->dev);
i2c_dev->hw = match->data;
i2c_dev->is_dvc = of_device_is_compatible(pdev->dev.of_node,
"nvidia,tegra20-i2c-dvc");
@@ -876,7 +864,7 @@ static struct platform_driver tegra_i2c_driver = {
.driver = {
.name = "tegra-i2c",
.owner = THIS_MODULE,
- .of_match_table = of_match_ptr(tegra_i2c_of_match),
+ .of_match_table = tegra_i2c_of_match,
.pm = TEGRA_I2C_PM,
},
};
diff --git a/drivers/i2c/busses/i2c-viperboard.c b/drivers/i2c/busses/i2c-viperboard.c
index f45c32c1ace6..c68450cd8d5f 100644
--- a/drivers/i2c/busses/i2c-viperboard.c
+++ b/drivers/i2c/busses/i2c-viperboard.c
@@ -421,11 +421,10 @@ error:
static int vprbrd_i2c_remove(struct platform_device *pdev)
{
struct vprbrd_i2c *vb_i2c = platform_get_drvdata(pdev);
- int ret;
- ret = i2c_del_adapter(&vb_i2c->i2c);
+ i2c_del_adapter(&vb_i2c->i2c);
- return ret;
+ return 0;
}
static struct platform_driver vprbrd_i2c_driver = {
diff --git a/drivers/i2c/busses/i2c-xiic.c b/drivers/i2c/busses/i2c-xiic.c
index 332c720fb3fe..3d0f0520c1b4 100644
--- a/drivers/i2c/busses/i2c-xiic.c
+++ b/drivers/i2c/busses/i2c-xiic.c
@@ -312,10 +312,8 @@ static void xiic_fill_tx_fifo(struct xiic_i2c *i2c)
/* last message in transfer -> STOP */
data |= XIIC_TX_DYN_STOP_MASK;
dev_dbg(i2c->adap.dev.parent, "%s TX STOP\n", __func__);
-
- xiic_setreg16(i2c, XIIC_DTR_REG_OFFSET, data);
- } else
- xiic_setreg8(i2c, XIIC_DTR_REG_OFFSET, data);
+ }
+ xiic_setreg16(i2c, XIIC_DTR_REG_OFFSET, data);
}
}
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 991d38daa87d..6b63cc7eb71e 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -27,7 +27,9 @@
#include <linux/module.h>
#include <linux/kernel.h>
+#include <linux/delay.h>
#include <linux/errno.h>
+#include <linux/gpio.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/init.h>
@@ -47,7 +49,7 @@
/* core_lock protects i2c_adapter_idr, and guarantees
that device detection, deletion of detected devices, and attach_adapter
- and detach_adapter calls are serialized */
+ calls are serialized */
static DEFINE_MUTEX(core_lock);
static DEFINE_IDR(i2c_adapter_idr);
@@ -91,7 +93,6 @@ static int i2c_device_match(struct device *dev, struct device_driver *drv)
return 0;
}
-#ifdef CONFIG_HOTPLUG
/* uevent helps with hotplug: modprobe -q $(MODALIAS) */
static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env)
@@ -105,9 +106,129 @@ static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env)
return 0;
}
-#else
-#define i2c_device_uevent NULL
-#endif /* CONFIG_HOTPLUG */
+/* i2c bus recovery routines */
+static int get_scl_gpio_value(struct i2c_adapter *adap)
+{
+ return gpio_get_value(adap->bus_recovery_info->scl_gpio);
+}
+
+static void set_scl_gpio_value(struct i2c_adapter *adap, int val)
+{
+ gpio_set_value(adap->bus_recovery_info->scl_gpio, val);
+}
+
+static int get_sda_gpio_value(struct i2c_adapter *adap)
+{
+ return gpio_get_value(adap->bus_recovery_info->sda_gpio);
+}
+
+static int i2c_get_gpios_for_recovery(struct i2c_adapter *adap)
+{
+ struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
+ struct device *dev = &adap->dev;
+ int ret = 0;
+
+ ret = gpio_request_one(bri->scl_gpio, GPIOF_OPEN_DRAIN |
+ GPIOF_OUT_INIT_HIGH, "i2c-scl");
+ if (ret) {
+ dev_warn(dev, "Can't get SCL gpio: %d\n", bri->scl_gpio);
+ return ret;
+ }
+
+ if (bri->get_sda) {
+ if (gpio_request_one(bri->sda_gpio, GPIOF_IN, "i2c-sda")) {
+ /* work without SDA polling */
+ dev_warn(dev, "Can't get SDA gpio: %d. Not using SDA polling\n",
+ bri->sda_gpio);
+ bri->get_sda = NULL;
+ }
+ }
+
+ return ret;
+}
+
+static void i2c_put_gpios_for_recovery(struct i2c_adapter *adap)
+{
+ struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
+
+ if (bri->get_sda)
+ gpio_free(bri->sda_gpio);
+
+ gpio_free(bri->scl_gpio);
+}
+
+/*
+ * We are generating clock pulses. ndelay() determines durating of clk pulses.
+ * We will generate clock with rate 100 KHz and so duration of both clock levels
+ * is: delay in ns = (10^6 / 100) / 2
+ */
+#define RECOVERY_NDELAY 5000
+#define RECOVERY_CLK_CNT 9
+
+static int i2c_generic_recovery(struct i2c_adapter *adap)
+{
+ struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
+ int i = 0, val = 1, ret = 0;
+
+ if (bri->prepare_recovery)
+ bri->prepare_recovery(bri);
+
+ /*
+ * By this time SCL is high, as we need to give 9 falling-rising edges
+ */
+ while (i++ < RECOVERY_CLK_CNT * 2) {
+ if (val) {
+ /* Break if SDA is high */
+ if (bri->get_sda && bri->get_sda(adap))
+ break;
+ /* SCL shouldn't be low here */
+ if (!bri->get_scl(adap)) {
+ dev_err(&adap->dev,
+ "SCL is stuck low, exit recovery\n");
+ ret = -EBUSY;
+ break;
+ }
+ }
+
+ val = !val;
+ bri->set_scl(adap, val);
+ ndelay(RECOVERY_NDELAY);
+ }
+
+ if (bri->unprepare_recovery)
+ bri->unprepare_recovery(bri);
+
+ return ret;
+}
+
+int i2c_generic_scl_recovery(struct i2c_adapter *adap)
+{
+ adap->bus_recovery_info->set_scl(adap, 1);
+ return i2c_generic_recovery(adap);
+}
+
+int i2c_generic_gpio_recovery(struct i2c_adapter *adap)
+{
+ int ret;
+
+ ret = i2c_get_gpios_for_recovery(adap);
+ if (ret)
+ return ret;
+
+ ret = i2c_generic_recovery(adap);
+ i2c_put_gpios_for_recovery(adap);
+
+ return ret;
+}
+
+int i2c_recover_bus(struct i2c_adapter *adap)
+{
+ if (!adap->bus_recovery_info)
+ return -EOPNOTSUPP;
+
+ dev_dbg(&adap->dev, "Trying i2c bus recovery\n");
+ return adap->bus_recovery_info->recover_bus(adap);
+}
static int i2c_device_probe(struct device *dev)
{
@@ -902,6 +1023,39 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
"Failed to create compatibility class link\n");
#endif
+ /* bus recovery specific initialization */
+ if (adap->bus_recovery_info) {
+ struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
+
+ if (!bri->recover_bus) {
+ dev_err(&adap->dev, "No recover_bus() found, not using recovery\n");
+ adap->bus_recovery_info = NULL;
+ goto exit_recovery;
+ }
+
+ /* Generic GPIO recovery */
+ if (bri->recover_bus == i2c_generic_gpio_recovery) {
+ if (!gpio_is_valid(bri->scl_gpio)) {
+ dev_err(&adap->dev, "Invalid SCL gpio, not using recovery\n");
+ adap->bus_recovery_info = NULL;
+ goto exit_recovery;
+ }
+
+ if (gpio_is_valid(bri->sda_gpio))
+ bri->get_sda = get_sda_gpio_value;
+ else
+ bri->get_sda = NULL;
+
+ bri->get_scl = get_scl_gpio_value;
+ bri->set_scl = set_scl_gpio_value;
+ } else if (!bri->set_scl || !bri->get_scl) {
+ /* Generic SCL recovery */
+ dev_err(&adap->dev, "No {get|set}_gpio() found, not using recovery\n");
+ adap->bus_recovery_info = NULL;
+ }
+ }
+
+exit_recovery:
/* create pre-declared device nodes */
if (adap->nr < __i2c_first_dynamic_bus_num)
i2c_scan_static_board_info(adap);
@@ -921,13 +1075,35 @@ out_list:
}
/**
+ * __i2c_add_numbered_adapter - i2c_add_numbered_adapter where nr is never -1
+ * @adap: the adapter to register (with adap->nr initialized)
+ * Context: can sleep
+ *
+ * See i2c_add_numbered_adapter() for details.
+ */
+static int __i2c_add_numbered_adapter(struct i2c_adapter *adap)
+{
+ int id;
+
+ mutex_lock(&core_lock);
+ id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1,
+ GFP_KERNEL);
+ mutex_unlock(&core_lock);
+ if (id < 0)
+ return id == -ENOSPC ? -EBUSY : id;
+
+ return i2c_register_adapter(adap);
+}
+
+/**
* i2c_add_adapter - declare i2c adapter, use dynamic bus number
* @adapter: the adapter to add
* Context: can sleep
*
* This routine is used to declare an I2C adapter when its bus number
- * doesn't matter. Examples: for I2C adapters dynamically added by
- * USB links or PCI plugin cards.
+ * doesn't matter or when its bus number is specified by an dt alias.
+ * Examples of bases when the bus number doesn't matter: I2C adapters
+ * dynamically added by USB links or PCI plugin cards.
*
* When this returns zero, a new bus number was allocated and stored
* in adap->nr, and the specified adapter became available for clients.
@@ -935,8 +1111,17 @@ out_list:
*/
int i2c_add_adapter(struct i2c_adapter *adapter)
{
+ struct device *dev = &adapter->dev;
int id;
+ if (dev->of_node) {
+ id = of_alias_get_id(dev->of_node, "i2c");
+ if (id >= 0) {
+ adapter->nr = id;
+ return __i2c_add_numbered_adapter(adapter);
+ }
+ }
+
mutex_lock(&core_lock);
id = idr_alloc(&i2c_adapter_idr, adapter,
__i2c_first_dynamic_bus_num, 0, GFP_KERNEL);
@@ -975,26 +1160,17 @@ EXPORT_SYMBOL(i2c_add_adapter);
*/
int i2c_add_numbered_adapter(struct i2c_adapter *adap)
{
- int id;
-
if (adap->nr == -1) /* -1 means dynamically assign bus id */
return i2c_add_adapter(adap);
- mutex_lock(&core_lock);
- id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1,
- GFP_KERNEL);
- mutex_unlock(&core_lock);
- if (id < 0)
- return id == -ENOSPC ? -EBUSY : id;
- return i2c_register_adapter(adap);
+ return __i2c_add_numbered_adapter(adap);
}
EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter);
-static int i2c_do_del_adapter(struct i2c_driver *driver,
+static void i2c_do_del_adapter(struct i2c_driver *driver,
struct i2c_adapter *adapter)
{
struct i2c_client *client, *_n;
- int res;
/* Remove the devices we created ourselves as the result of hardware
* probing (using a driver's detect method) */
@@ -1006,16 +1182,6 @@ static int i2c_do_del_adapter(struct i2c_driver *driver,
i2c_unregister_device(client);
}
}
-
- if (!driver->detach_adapter)
- return 0;
- dev_warn(&adapter->dev, "%s: detach_adapter method is deprecated\n",
- driver->driver.name);
- res = driver->detach_adapter(adapter);
- if (res)
- dev_err(&adapter->dev, "detach_adapter failed (%d) "
- "for driver [%s]\n", res, driver->driver.name);
- return res;
}
static int __unregister_client(struct device *dev, void *dummy)
@@ -1036,7 +1202,8 @@ static int __unregister_dummy(struct device *dev, void *dummy)
static int __process_removed_adapter(struct device_driver *d, void *data)
{
- return i2c_do_del_adapter(to_i2c_driver(d), data);
+ i2c_do_del_adapter(to_i2c_driver(d), data);
+ return 0;
}
/**
@@ -1047,9 +1214,8 @@ static int __process_removed_adapter(struct device_driver *d, void *data)
* This unregisters an I2C adapter which was previously registered
* by @i2c_add_adapter or @i2c_add_numbered_adapter.
*/
-int i2c_del_adapter(struct i2c_adapter *adap)
+void i2c_del_adapter(struct i2c_adapter *adap)
{
- int res = 0;
struct i2c_adapter *found;
struct i2c_client *client, *next;
@@ -1060,16 +1226,14 @@ int i2c_del_adapter(struct i2c_adapter *adap)
if (found != adap) {
pr_debug("i2c-core: attempting to delete unregistered "
"adapter [%s]\n", adap->name);
- return -EINVAL;
+ return;
}
/* Tell drivers about this removal */
mutex_lock(&core_lock);
- res = bus_for_each_drv(&i2c_bus_type, NULL, adap,
+ bus_for_each_drv(&i2c_bus_type, NULL, adap,
__process_removed_adapter);
mutex_unlock(&core_lock);
- if (res)
- return res;
/* Remove devices instantiated from sysfs */
mutex_lock_nested(&adap->userspace_clients_lock,
@@ -1088,8 +1252,8 @@ int i2c_del_adapter(struct i2c_adapter *adap)
* we can't remove the dummy devices during the first pass: they
* could have been instantiated by real devices wishing to clean
* them up properly, so we give them a chance to do that first. */
- res = device_for_each_child(&adap->dev, NULL, __unregister_client);
- res = device_for_each_child(&adap->dev, NULL, __unregister_dummy);
+ device_for_each_child(&adap->dev, NULL, __unregister_client);
+ device_for_each_child(&adap->dev, NULL, __unregister_dummy);
#ifdef CONFIG_I2C_COMPAT
class_compat_remove_link(i2c_adapter_compat_class, &adap->dev,
@@ -1114,8 +1278,6 @@ int i2c_del_adapter(struct i2c_adapter *adap)
/* Clear the device structure in case this adapter is ever going to be
added again */
memset(&adap->dev, 0, sizeof(adap->dev));
-
- return 0;
}
EXPORT_SYMBOL(i2c_del_adapter);
@@ -1185,9 +1347,9 @@ EXPORT_SYMBOL(i2c_register_driver);
static int __process_removed_driver(struct device *dev, void *data)
{
- if (dev->type != &i2c_adapter_type)
- return 0;
- return i2c_do_del_adapter(data, to_i2c_adapter(dev));
+ if (dev->type == &i2c_adapter_type)
+ i2c_do_del_adapter(data, to_i2c_adapter(dev));
+ return 0;
}
/**
diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c
index d94e0ce78277..7409ebb33c47 100644
--- a/drivers/i2c/i2c-mux.c
+++ b/drivers/i2c/i2c-mux.c
@@ -191,17 +191,12 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
}
EXPORT_SYMBOL_GPL(i2c_add_mux_adapter);
-int i2c_del_mux_adapter(struct i2c_adapter *adap)
+void i2c_del_mux_adapter(struct i2c_adapter *adap)
{
struct i2c_mux_priv *priv = adap->algo_data;
- int ret;
- ret = i2c_del_adapter(adap);
- if (ret < 0)
- return ret;
+ i2c_del_adapter(adap);
kfree(priv);
-
- return 0;
}
EXPORT_SYMBOL_GPL(i2c_del_mux_adapter);
diff --git a/drivers/i2c/muxes/Kconfig b/drivers/i2c/muxes/Kconfig
index 0be5b83c08fa..5faf244d2476 100644
--- a/drivers/i2c/muxes/Kconfig
+++ b/drivers/i2c/muxes/Kconfig
@@ -5,6 +5,18 @@
menu "Multiplexer I2C Chip support"
depends on I2C_MUX
+config I2C_ARB_GPIO_CHALLENGE
+ tristate "GPIO-based I2C arbitration"
+ depends on GENERIC_GPIO && OF
+ help
+ If you say yes to this option, support will be included for an
+ I2C multimaster arbitration scheme using GPIOs and a challenge &
+ response mechanism where masters have to claim the bus by asserting
+ a GPIO.
+
+ This driver can also be built as a module. If so, the module
+ will be called i2c-arb-gpio-challenge.
+
config I2C_MUX_GPIO
tristate "GPIO-based I2C multiplexer"
depends on GENERIC_GPIO
diff --git a/drivers/i2c/muxes/Makefile b/drivers/i2c/muxes/Makefile
index 76da8692afff..465778b5d5dc 100644
--- a/drivers/i2c/muxes/Makefile
+++ b/drivers/i2c/muxes/Makefile
@@ -1,6 +1,8 @@
#
# Makefile for multiplexer I2C chip drivers.
+obj-$(CONFIG_I2C_ARB_GPIO_CHALLENGE) += i2c-arb-gpio-challenge.o
+
obj-$(CONFIG_I2C_MUX_GPIO) += i2c-mux-gpio.o
obj-$(CONFIG_I2C_MUX_PCA9541) += i2c-mux-pca9541.o
obj-$(CONFIG_I2C_MUX_PCA954x) += i2c-mux-pca954x.o
diff --git a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
new file mode 100644
index 000000000000..210b6f7b9028
--- /dev/null
+++ b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
@@ -0,0 +1,251 @@
+/*
+ * GPIO-based I2C Arbitration Using a Challenge & Response Mechanism
+ *
+ * Copyright (C) 2012 Google, Inc
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/gpio.h>
+#include <linux/kernel.h>
+#include <linux/i2c.h>
+#include <linux/i2c-mux.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/of_i2c.h>
+#include <linux/of_gpio.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+
+/**
+ * struct i2c_arbitrator_data - Driver data for I2C arbitrator
+ *
+ * @parent: Parent adapter
+ * @child: Child bus
+ * @our_gpio: GPIO we'll use to claim.
+ * @our_gpio_release: 0 if active high; 1 if active low; AKA if the GPIO ==
+ * this then consider it released.
+ * @their_gpio: GPIO that the other side will use to claim.
+ * @their_gpio_release: 0 if active high; 1 if active low; AKA if the GPIO ==
+ * this then consider it released.
+ * @slew_delay_us: microseconds to wait for a GPIO to go high.
+ * @wait_retry_us: we'll attempt another claim after this many microseconds.
+ * @wait_free_us: we'll give up after this many microseconds.
+ */
+
+struct i2c_arbitrator_data {
+ struct i2c_adapter *parent;
+ struct i2c_adapter *child;
+ int our_gpio;
+ int our_gpio_release;
+ int their_gpio;
+ int their_gpio_release;
+ unsigned int slew_delay_us;
+ unsigned int wait_retry_us;
+ unsigned int wait_free_us;
+};
+
+
+/**
+ * i2c_arbitrator_select - claim the I2C bus
+ *
+ * Use the GPIO-based signalling protocol; return -EBUSY if we fail.
+ */
+static int i2c_arbitrator_select(struct i2c_adapter *adap, void *data, u32 chan)
+{
+ const struct i2c_arbitrator_data *arb = data;
+ unsigned long stop_retry, stop_time;
+
+ /* Start a round of trying to claim the bus */
+ stop_time = jiffies + usecs_to_jiffies(arb->wait_free_us) + 1;
+ do {
+ /* Indicate that we want to claim the bus */
+ gpio_set_value(arb->our_gpio, !arb->our_gpio_release);
+ udelay(arb->slew_delay_us);
+
+ /* Wait for the other master to release it */
+ stop_retry = jiffies + usecs_to_jiffies(arb->wait_retry_us) + 1;
+ while (time_before(jiffies, stop_retry)) {
+ int gpio_val = !!gpio_get_value(arb->their_gpio);
+
+ if (gpio_val == arb->their_gpio_release) {
+ /* We got it, so return */
+ return 0;
+ }
+
+ usleep_range(50, 200);
+ }
+
+ /* It didn't release, so give up, wait, and try again */
+ gpio_set_value(arb->our_gpio, arb->our_gpio_release);
+
+ usleep_range(arb->wait_retry_us, arb->wait_retry_us * 2);
+ } while (time_before(jiffies, stop_time));
+
+ /* Give up, release our claim */
+ gpio_set_value(arb->our_gpio, arb->our_gpio_release);
+ udelay(arb->slew_delay_us);
+ dev_err(&adap->dev, "Could not claim bus, timeout\n");
+ return -EBUSY;
+}
+
+/**
+ * i2c_arbitrator_deselect - release the I2C bus
+ *
+ * Release the I2C bus using the GPIO-based signalling protocol.
+ */
+static int i2c_arbitrator_deselect(struct i2c_adapter *adap, void *data,
+ u32 chan)
+{
+ const struct i2c_arbitrator_data *arb = data;
+
+ /* Release the bus and wait for the other master to notice */
+ gpio_set_value(arb->our_gpio, arb->our_gpio_release);
+ udelay(arb->slew_delay_us);
+
+ return 0;
+}
+
+static int i2c_arbitrator_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct device_node *parent_np;
+ struct i2c_arbitrator_data *arb;
+ enum of_gpio_flags gpio_flags;
+ unsigned long out_init;
+ int ret;
+
+ /* We only support probing from device tree; no platform_data */
+ if (!np) {
+ dev_err(dev, "Cannot find device tree node\n");
+ return -ENODEV;
+ }
+ if (dev->platform_data) {
+ dev_err(dev, "Platform data is not supported\n");
+ return -EINVAL;
+ }
+
+ arb = devm_kzalloc(dev, sizeof(*arb), GFP_KERNEL);
+ if (!arb) {
+ dev_err(dev, "Cannot allocate i2c_arbitrator_data\n");
+ return -ENOMEM;
+ }
+ platform_set_drvdata(pdev, arb);
+
+ /* Request GPIOs */
+ ret = of_get_named_gpio_flags(np, "our-claim-gpio", 0, &gpio_flags);
+ if (!gpio_is_valid(ret)) {
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "Error getting our-claim-gpio\n");
+ return ret;
+ }
+ arb->our_gpio = ret;
+ arb->our_gpio_release = !!(gpio_flags & OF_GPIO_ACTIVE_LOW);
+ out_init = (gpio_flags & OF_GPIO_ACTIVE_LOW) ?
+ GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW;
+ ret = devm_gpio_request_one(dev, arb->our_gpio, out_init,
+ "our-claim-gpio");
+ if (ret) {
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "Error requesting our-claim-gpio\n");
+ return ret;
+ }
+
+ ret = of_get_named_gpio_flags(np, "their-claim-gpios", 0, &gpio_flags);
+ if (!gpio_is_valid(ret)) {
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "Error getting their-claim-gpio\n");
+ return ret;
+ }
+ arb->their_gpio = ret;
+ arb->their_gpio_release = !!(gpio_flags & OF_GPIO_ACTIVE_LOW);
+ ret = devm_gpio_request_one(dev, arb->their_gpio, GPIOF_IN,
+ "their-claim-gpio");
+ if (ret) {
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "Error requesting their-claim-gpio\n");
+ return ret;
+ }
+
+ /* At the moment we only support a single two master (us + 1 other) */
+ if (gpio_is_valid(of_get_named_gpio(np, "their-claim-gpios", 1))) {
+ dev_err(dev, "Only one other master is supported\n");
+ return -EINVAL;
+ }
+
+ /* Arbitration parameters */
+ if (of_property_read_u32(np, "slew-delay-us", &arb->slew_delay_us))
+ arb->slew_delay_us = 10;
+ if (of_property_read_u32(np, "wait-retry-us", &arb->wait_retry_us))
+ arb->wait_retry_us = 3000;
+ if (of_property_read_u32(np, "wait-free-us", &arb->wait_free_us))
+ arb->wait_free_us = 50000;
+
+ /* Find our parent */
+ parent_np = of_parse_phandle(np, "i2c-parent", 0);
+ if (!parent_np) {
+ dev_err(dev, "Cannot parse i2c-parent\n");
+ return -EINVAL;
+ }
+ arb->parent = of_find_i2c_adapter_by_node(parent_np);
+ if (!arb->parent) {
+ dev_err(dev, "Cannot find parent bus\n");
+ return -EINVAL;
+ }
+
+ /* Actually add the mux adapter */
+ arb->child = i2c_add_mux_adapter(arb->parent, dev, arb, 0, 0, 0,
+ i2c_arbitrator_select,
+ i2c_arbitrator_deselect);
+ if (!arb->child) {
+ dev_err(dev, "Failed to add adapter\n");
+ ret = -ENODEV;
+ i2c_put_adapter(arb->parent);
+ }
+
+ return ret;
+}
+
+static int i2c_arbitrator_remove(struct platform_device *pdev)
+{
+ struct i2c_arbitrator_data *arb = platform_get_drvdata(pdev);
+
+ i2c_del_mux_adapter(arb->child);
+ i2c_put_adapter(arb->parent);
+
+ return 0;
+}
+
+static const struct of_device_id i2c_arbitrator_of_match[] = {
+ { .compatible = "i2c-arb-gpio-challenge", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, i2c_arbitrator_of_match);
+
+static struct platform_driver i2c_arbitrator_driver = {
+ .probe = i2c_arbitrator_probe,
+ .remove = i2c_arbitrator_remove,
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "i2c-arb-gpio-challenge",
+ .of_match_table = of_match_ptr(i2c_arbitrator_of_match),
+ },
+};
+
+module_platform_driver(i2c_arbitrator_driver);
+
+MODULE_DESCRIPTION("GPIO-based I2C Arbitration");
+MODULE_AUTHOR("Doug Anderson <dianders@chromium.org>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:i2c-arb-gpio-challenge");
diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
index abc2e55aa243..5a0ce0081dce 100644
--- a/drivers/i2c/muxes/i2c-mux-gpio.c
+++ b/drivers/i2c/muxes/i2c-mux-gpio.c
@@ -201,10 +201,21 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
for (i = 0; i < mux->data.n_gpios; i++) {
ret = gpio_request(gpio_base + mux->data.gpios[i], "i2c-mux-gpio");
- if (ret)
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to request GPIO %d\n",
+ mux->data.gpios[i]);
goto err_request_gpio;
- gpio_direction_output(gpio_base + mux->data.gpios[i],
- initial_state & (1 << i));
+ }
+
+ ret = gpio_direction_output(gpio_base + mux->data.gpios[i],
+ initial_state & (1 << i));
+ if (ret) {
+ dev_err(&pdev->dev,
+ "Failed to set direction of GPIO %d to output\n",
+ mux->data.gpios[i]);
+ i++; /* gpio_request above succeeded, so must free */
+ goto err_request_gpio;
+ }
}
for (i = 0; i < mux->data.n_values; i++) {
diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
index 8e4387235b69..a531d801dbe4 100644
--- a/drivers/i2c/muxes/i2c-mux-pca954x.c
+++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
@@ -262,13 +262,11 @@ static int pca954x_remove(struct i2c_client *client)
{
struct pca954x *data = i2c_get_clientdata(client);
const struct chip_desc *chip = &chips[data->type];
- int i, err;
+ int i;
for (i = 0; i < chip->nchans; ++i)
if (data->virt_adaps[i]) {
- err = i2c_del_mux_adapter(data->virt_adaps[i]);
- if (err)
- return err;
+ i2c_del_mux_adapter(data->virt_adaps[i]);
data->virt_adaps[i] = NULL;
}