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authorWolfram Sang <wsa+renesas@sang-engineering.com>2014-12-16 13:31:25 +0100
committerWolfram Sang <wsa@the-dreams.de>2014-12-17 19:26:07 +0100
commite844a7997dfbce687c7afa9d40f8a3b278e08735 (patch)
tree10b94485c39112e0bdd4b81f1360bea1a281a2cc /drivers
parent00d8689b85a7bb37cc57ba4c40bd46325f51ced4 (diff)
i2c: sh_mobile: refactor DMA setup
Refactor DMA setup to keep the errno so we can implement better deferred probe support in the next step. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/i2c/busses/i2c-sh_mobile.c35
1 files changed, 16 insertions, 19 deletions
diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c
index d7efaf44868b..b49e946b2940 100644
--- a/drivers/i2c/busses/i2c-sh_mobile.c
+++ b/drivers/i2c/busses/i2c-sh_mobile.c
@@ -548,7 +548,7 @@ static void sh_mobile_i2c_xfer_dma(struct sh_mobile_i2c_data *pd)
dma_addr_t dma_addr;
dma_cookie_t cookie;
- if (!chan)
+ if (IS_ERR(chan))
return;
dma_addr = dma_map_single(chan->device->dev, pd->msg->buf, pd->msg->len, dir);
@@ -747,21 +747,18 @@ static const struct of_device_id sh_mobile_i2c_dt_ids[] = {
};
MODULE_DEVICE_TABLE(of, sh_mobile_i2c_dt_ids);
-static int sh_mobile_i2c_request_dma_chan(struct device *dev, enum dma_transfer_direction dir,
- dma_addr_t port_addr, struct dma_chan **chan_ptr)
+static struct dma_chan *sh_mobile_i2c_request_dma_chan(struct device *dev,
+ enum dma_transfer_direction dir, dma_addr_t port_addr)
{
struct dma_chan *chan;
struct dma_slave_config cfg;
char *chan_name = dir == DMA_MEM_TO_DEV ? "tx" : "rx";
int ret;
- *chan_ptr = NULL;
-
chan = dma_request_slave_channel_reason(dev, chan_name);
if (IS_ERR(chan)) {
- ret = PTR_ERR(chan);
dev_dbg(dev, "request_channel failed for %s (%d)\n", chan_name, ret);
- return ret;
+ return chan;
}
memset(&cfg, 0, sizeof(cfg));
@@ -778,25 +775,23 @@ static int sh_mobile_i2c_request_dma_chan(struct device *dev, enum dma_transfer_
if (ret) {
dev_dbg(dev, "slave_config failed for %s (%d)\n", chan_name, ret);
dma_release_channel(chan);
- return ret;
+ return ERR_PTR(ret);
}
- *chan_ptr = chan;
-
dev_dbg(dev, "got DMA channel for %s\n", chan_name);
- return 0;
+ return chan;
}
static void sh_mobile_i2c_release_dma(struct sh_mobile_i2c_data *pd)
{
- if (pd->dma_tx) {
+ if (!IS_ERR(pd->dma_tx)) {
dma_release_channel(pd->dma_tx);
- pd->dma_tx = NULL;
+ pd->dma_tx = ERR_PTR(-EPROBE_DEFER);
}
- if (pd->dma_rx) {
+ if (!IS_ERR(pd->dma_rx)) {
dma_release_channel(pd->dma_rx);
- pd->dma_rx = NULL;
+ pd->dma_rx = ERR_PTR(-EPROBE_DEFER);
}
}
@@ -889,13 +884,15 @@ static int sh_mobile_i2c_probe(struct platform_device *dev)
/* Init DMA */
sg_init_table(&pd->sg, 1);
pd->dma_direction = DMA_NONE;
- ret = sh_mobile_i2c_request_dma_chan(pd->dev, DMA_DEV_TO_MEM,
- res->start + ICDR, &pd->dma_rx);
+ pd->dma_rx = sh_mobile_i2c_request_dma_chan(pd->dev, DMA_DEV_TO_MEM,
+ res->start + ICDR);
+ ret = PTR_ERR(pd->dma_rx);
if (ret == -EPROBE_DEFER)
return ret;
- ret = sh_mobile_i2c_request_dma_chan(pd->dev, DMA_MEM_TO_DEV,
- res->start + ICDR, &pd->dma_tx);
+ pd->dma_tx = sh_mobile_i2c_request_dma_chan(pd->dev, DMA_MEM_TO_DEV,
+ res->start + ICDR);
+ ret = PTR_ERR(pd->dma_tx);
if (ret == -EPROBE_DEFER) {
sh_mobile_i2c_release_dma(pd);
return ret;