Kernel driver for SSL3250A flash/torch camera device.

Change-Id: Id5cb40c9823c7fcfd26e45e4608c45b16a2d431a
Reviewed-on: http://git-master/r/21351
Reviewed-by: Erik M Lilliebjerg <elilliebjerg@nvidia.com>
Tested-by: Erik M Lilliebjerg <elilliebjerg@nvidia.com>
Reviewed-by: George Bauernschmidt <georgeb@nvidia.com>
Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>

3 files changed, 316 insertions, 0 deletions

diff --git a/drivers/media/video/tegra/Kconfig b/drivers/media/video/tegra/Kconfig
index edf6b5b3c1d3..d6e5368f5652 100644
--- a/drivers/media/video/tegra/Kconfig
+++ b/drivers/media/video/tegra/Kconfig
@@ -23,3 +23,10 @@ config VIDEO_OV2710
           This is a driver for the Omnivision OV2710 camera sensor
           for use with the tegra isp.
 
+config TORCH_SSL3250A
+        tristate "SSL3250A flash/torch support"
+        depends on I2C && ARCH_TEGRA
+        ---help---
+          This is a driver for the SSL3250A flash/torch camera device
+          for use with the tegra isp.
+
diff --git a/drivers/media/video/tegra/Makefile b/drivers/media/video/tegra/Makefile
index ca43f67445f1..1aacd5ef07d2 100644
--- a/drivers/media/video/tegra/Makefile
+++ b/drivers/media/video/tegra/Makefile
@@ -5,4 +5,5 @@ obj-y				+= avp/
 obj-$(CONFIG_TEGRA_CAMERA)	+= tegra_camera.o
 obj-$(CONFIG_VIDEO_OV5650)	+= ov5650.o
 obj-$(CONFIG_VIDEO_OV2710)	+= ov2710.o
+obj-$(CONFIG_TORCH_SSL3250A)	+= ssl3250a.o
 
diff --git a/drivers/media/video/tegra/ssl3250a.c b/drivers/media/video/tegra/ssl3250a.c
new file mode 100644
index 000000000000..f2082a5c193c
--- /dev/null
+++ b/drivers/media/video/tegra/ssl3250a.c
@@ -0,0 +1,308 @@
+/*
+ * ssl3250a.c - ssl3250a flash/torch kernel driver
+ *
+ * Copyright (C) 2011 NVIDIA Corp.
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+
+#include <linux/fs.h>
+#include <linux/i2c.h>
+#include <linux/miscdevice.h>
+#include <linux/slab.h>
+#include <media/ssl3250a.h>
+
+#define SSL3250A_I2C_REG_AMP		0x00
+#define SSL3250A_I2C_REG_TMR		0x01
+#define SSL3250A_I2C_REG_STRB		0x02
+#define SSL3250A_I2C_REG_STS		0x03
+
+
+enum {
+	SSL3250A_GPIO_ACT,
+	SSL3250A_GPIO_EN1,
+	SSL3250A_GPIO_EN2,
+	SSL3250A_GPIO_STRB,
+};
+
+struct ssl3250a_info {
+	struct i2c_client *i2c_client;
+	struct ssl3250a_platform_data *pdata;
+};
+
+static struct ssl3250a_info *info;
+
+static int ssl3250a_gpio(u8 gpio, u8 val)
+{
+	switch (gpio) {
+	case SSL3250A_GPIO_ACT:
+		if (info->pdata && info->pdata->gpio_act)
+			return info->pdata->gpio_act(val);
+		return -1;
+
+	case SSL3250A_GPIO_EN1:
+		if (info->pdata && info->pdata->gpio_en1)
+			return info->pdata->gpio_en1(val);
+		return -1;
+
+	case SSL3250A_GPIO_EN2:
+		if (info->pdata && info->pdata->gpio_en2)
+			return info->pdata->gpio_en2(val);
+		return -1;
+
+	case SSL3250A_GPIO_STRB:
+		if (info->pdata && info->pdata->gpio_strb)
+			return info->pdata->gpio_strb(val);
+
+	default:
+		return -1;
+	}
+}
+
+static int ssl3250a_get_reg(u8 addr, u8 *val)
+{
+	struct i2c_client *client = info->i2c_client;
+	struct i2c_msg msg[2];
+	unsigned char data[2];
+
+	msg[0].addr = client->addr;
+	msg[0].flags = 0;
+	msg[0].len = 1;
+	msg[0].buf = data;
+
+	data[0] = (u8) (addr);
+
+	msg[1].addr = client->addr;
+	msg[1].flags = I2C_M_RD;
+	msg[1].len = 1;
+	msg[1].buf = data + 1;
+
+	*val = 0;
+
+	if (i2c_transfer(client->adapter, msg, 2) == 2) {
+		*val = data[1];
+		return 0;
+	} else {
+		return -1;
+	}
+}
+
+static int ssl3250a_set_reg(u8 addr, u8 val)
+{
+	struct i2c_client *client = info->i2c_client;
+	struct i2c_msg msg;
+	unsigned char data[2];
+
+	data[0] = (u8) (addr);
+	data[1] = (u8) (val);
+	msg.addr = client->addr;
+	msg.flags = 0;
+	msg.len = 2;
+	msg.buf = data;
+
+	if (i2c_transfer(client->adapter, &msg, 1) == 1)
+		return 0;
+	else
+		return -1;
+}
+
+static long ssl3250a_ioctl(
+	struct file *file,
+	unsigned int cmd,
+	unsigned long arg)
+{
+	u8 val = (u8)arg;
+	u8 reg;
+
+	switch (cmd) {
+	case SSL3250A_IOCTL_MODE_SHUTDOWN:
+		ssl3250a_gpio(SSL3250A_GPIO_ACT, 0);
+		return 0;
+
+	case SSL3250A_IOCTL_MODE_STANDBY:
+		ssl3250a_gpio(SSL3250A_GPIO_ACT, 1);
+		if (info->pdata->config & 0x01) {	/*0:0 0=I2C, 1=GPIO*/
+			ssl3250a_gpio(SSL3250A_GPIO_EN1, 0);
+			ssl3250a_gpio(SSL3250A_GPIO_EN2, 0);
+			return 0;
+		} else {
+			return ssl3250a_set_reg(SSL3250A_I2C_REG_AMP, 0x00);
+		}
+
+/* Amp limit for torch, flash, and LED is controlled by external circuitry in
+ * GPIO mode.  In I2C mode amp limit is controlled by chip registers and the
+ * limit values are in the board-sensors file.
+ */
+	case SSL3250A_IOTCL_MODE_TORCH:
+		ssl3250a_gpio(SSL3250A_GPIO_ACT, 1);
+		if (info->pdata->config & 0x01) {	/*0:0 0=I2C, 1=GPIO*/
+			ssl3250a_gpio(SSL3250A_GPIO_EN1, 0);
+			ssl3250a_gpio(SSL3250A_GPIO_EN2, 1);
+			return 0;
+		} else {
+			if (val > info->pdata->max_amp_torch)
+				val = info->pdata->max_amp_torch;
+			val = ((val << 3) & 0xF8);	/*7:3=torch amps*/
+			if (!ssl3250a_get_reg(SSL3250A_I2C_REG_AMP, &reg)) {
+				val = val | (reg & 0x07); /*shared w/ LED 2:0*/
+				return ssl3250a_set_reg(SSL3250A_I2C_REG_AMP,
+							val);
+			} else {
+				return -1;
+			}
+		}
+
+	case SSL3250A_IOCTL_MODE_FLASH:
+		ssl3250a_gpio(SSL3250A_GPIO_ACT, 1);
+		if (info->pdata->config & 0x01) {	/*0:0 0=I2C, 1=GPIO*/
+			ssl3250a_gpio(SSL3250A_GPIO_EN1, 1);
+			ssl3250a_gpio(SSL3250A_GPIO_EN2, 1);
+			return 0;
+		} else {
+			if (val != 0)			/*if 0 then flash=off*/
+				val = val + 11;		/*flash starts at 12*/
+			if (val > info->pdata->max_amp_flash)
+				val = info->pdata->max_amp_flash;
+			val = ((val << 3) & 0xF8);	/*7:3=flash amps*/
+			if (!ssl3250a_get_reg(SSL3250A_I2C_REG_AMP, &reg)) {
+				val = val | (reg & 0x07); /*shared w/ LED 2:0*/
+				return ssl3250a_set_reg(SSL3250A_I2C_REG_AMP,
+							val);
+			} else {
+				return -1;
+			}
+		}
+
+	case SSL3250A_IOCTL_MODE_LED:
+		ssl3250a_gpio(SSL3250A_GPIO_ACT, 1);
+		if (info->pdata->config & 0x01) {	/*0:0 0=I2C, 1=GPIO*/
+			ssl3250a_gpio(SSL3250A_GPIO_EN1, 1);
+			ssl3250a_gpio(SSL3250A_GPIO_EN2, 0);
+			return 0;
+		} else {
+			if (val > info->pdata->max_amp_indic)
+				val = info->pdata->max_amp_indic;
+			val = (val & 0x07);		/*2:0=LED amps*/
+			if (!ssl3250a_get_reg(SSL3250A_I2C_REG_AMP, &reg)) {
+				val = val | (reg & 0xF8); /*shared w/ 7:3*/
+				return ssl3250a_set_reg(SSL3250A_I2C_REG_AMP,
+							val);
+			} else {
+				return -1;
+			}
+		}
+
+	case SSL3250A_IOCTL_STRB:
+		if (val)
+			val = 0x01;			/*bit 0=I2C, >0=GPIO*/
+		/* if STRB GPIO use that regardless of operation mode */
+		if (!ssl3250a_gpio(SSL3250A_GPIO_STRB, val))
+			return 0;
+		if (!info->pdata->config & 0x01)	/*0:0 0=I2C, 1=GPIO*/
+			return ssl3250a_set_reg(SSL3250A_I2C_REG_STRB, val);
+		else
+			return -1;
+
+	case SSL3250A_IOCTL_TIMER:
+		if (!info->pdata->config & 0x01)	/*if I2C mode*/
+			return ssl3250a_set_reg(SSL3250A_I2C_REG_TMR, val);
+
+	default:
+		return -1;
+	}
+}
+
+
+static int ssl3250a_open(struct inode *inode, struct file *file)
+{
+	file->private_data = info;
+	if (info->pdata && info->pdata->init)
+		info->pdata->init();
+	return 0;
+}
+
+int ssl3250a_release(struct inode *inode, struct file *file)
+{
+	if (info->pdata && info->pdata->exit)
+		info->pdata->exit();
+	file->private_data = NULL;
+	return 0;
+}
+
+
+static const struct file_operations ssl3250a_fileops = {
+	.owner = THIS_MODULE,
+	.open = ssl3250a_open,
+	.unlocked_ioctl = ssl3250a_ioctl,
+	.release = ssl3250a_release,
+};
+
+static struct miscdevice ssl3250a_device = {
+	.minor = MISC_DYNAMIC_MINOR,
+	.name = "ssl3250a",
+	.fops = &ssl3250a_fileops,
+};
+
+static int ssl3250a_probe(
+	struct i2c_client *client,
+	const struct i2c_device_id *id)
+{
+	int err;
+	info = kzalloc(sizeof(struct ssl3250a_info), GFP_KERNEL);
+	if (!info) {
+		pr_err("ssl3250a: Unable to allocate memory!\n");
+		return -ENOMEM;
+	}
+	err = misc_register(&ssl3250a_device);
+	if (err) {
+		pr_err("ssl3250a: Unable to register misc device!\n");
+		kfree(info);
+		return err;
+	}
+	info->pdata = client->dev.platform_data;
+	info->i2c_client = client;
+	i2c_set_clientdata(client, info);
+	return 0;
+}
+
+static int ssl3250a_remove(struct i2c_client *client)
+{
+	info = i2c_get_clientdata(client);
+	misc_deregister(&ssl3250a_device);
+	kfree(info);
+	return 0;
+}
+
+static const struct i2c_device_id ssl3250a_id[] = {
+	{ "ssl3250a", 0 },
+	{ },
+};
+
+MODULE_DEVICE_TABLE(i2c, ssl3250a_id);
+
+static struct i2c_driver ssl3250a_i2c_driver = {
+	.driver = {
+		.name = "ssl3250a",
+		.owner = THIS_MODULE,
+	},
+	.probe = ssl3250a_probe,
+	.remove = ssl3250a_remove,
+	.id_table = ssl3250a_id,
+};
+
+static int __init ssl3250a_init(void)
+{
+	return i2c_add_driver(&ssl3250a_i2c_driver);
+}
+
+static void __exit ssl3250a_exit(void)
+{
+	i2c_del_driver(&ssl3250a_i2c_driver);
+}
+
+module_init(ssl3250a_init);
+module_exit(ssl3250a_exit);
+