[media] V4L: s5c73m3: Add device tree support

This patch adds the V4L2 asynchronous subdev registration and
device tree support. Common clock API is used to control the
sensor master clock from within the subdev.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/i2c/s5c73m3/s5c73m3-core.c

@@ -15,7 +15,7 @@
  * GNU General Public License for more details.
  */
 
-#include <linux/sizes.h>
+#include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/firmware.h>
 #include <linux/gpio.h>
@@ -23,7 +23,9 @@
 #include <linux/init.h>
 #include <linux/media.h>
 #include <linux/module.h>
+#include <linux/of_gpio.h>
 #include <linux/regulator/consumer.h>
+#include <linux/sizes.h>
 #include <linux/slab.h>
 #include <linux/spi/spi.h>
 #include <linux/videodev2.h>
@@ -33,6 +35,7 @@
 #include <media/v4l2-subdev.h>
 #include <media/v4l2-mediabus.h>
 #include <media/s5c73m3.h>
+#include <media/v4l2-of.h>
 
 #include "s5c73m3.h"
 
@@ -46,6 +49,8 @@ static int update_fw;
 module_param(update_fw, int, 0644);
 
 #define S5C73M3_EMBEDDED_DATA_MAXLEN	SZ_4K
+#define S5C73M3_MIPI_DATA_LANES		4
+#define S5C73M3_CLK_NAME		"cis_extclk"
 
 static const char * const s5c73m3_supply_names[S5C73M3_MAX_SUPPLIES] = {
 	"vdd-int",	/* Digital Core supply (1.2V), CAM_ISP_CORE_1.2V */
@@ -1355,9 +1360,20 @@ static int __s5c73m3_power_on(struct s5c73m3 *state)
 	for (i = 0; i < S5C73M3_MAX_SUPPLIES; i++) {
 		ret = regulator_enable(state->supplies[i].consumer);
 		if (ret)
-			goto err;
+			goto err_reg_dis;
 	}
 
+	ret = clk_set_rate(state->clock, state->mclk_frequency);
+	if (ret < 0)
+		goto err_reg_dis;
+
+	ret = clk_prepare_enable(state->clock);
+	if (ret < 0)
+		goto err_reg_dis;
+
+	v4l2_dbg(1, s5c73m3_dbg, &state->oif_sd, "clock frequency: %ld\n",
+					clk_get_rate(state->clock));
+
 	s5c73m3_gpio_deassert(state, STBY);
 	usleep_range(100, 200);
 
@@ -1365,7 +1381,8 @@ static int __s5c73m3_power_on(struct s5c73m3 *state)
 	usleep_range(50, 100);
 
 	return 0;
-err:
+
+err_reg_dis:
 	for (--i; i >= 0; i--)
 		regulator_disable(state->supplies[i].consumer);
 	return ret;
@@ -1380,6 +1397,9 @@ static int __s5c73m3_power_off(struct s5c73m3 *state)
 
 	if (s5c73m3_gpio_assert(state, STBY))
 		usleep_range(100, 200);
+
+	clk_disable_unprepare(state->clock);
+
 	state->streaming = 0;
 	state->isp_ready = 0;
 
@@ -1388,6 +1408,7 @@ static int __s5c73m3_power_off(struct s5c73m3 *state)
 		if (ret)
 			goto err;
 	}
+
 	return 0;
 err:
 	for (++i; i < S5C73M3_MAX_SUPPLIES; i++) {
@@ -1396,6 +1417,8 @@ err:
 			v4l2_err(&state->oif_sd, "Failed to reenable %s: %d\n",
 				 state->supplies[i].supply, r);
 	}
+
+	clk_prepare_enable(state->clock);
 	return ret;
 }
 
@@ -1451,17 +1474,6 @@ static int s5c73m3_oif_registered(struct v4l2_subdev *sd)
 			S5C73M3_JPEG_PAD, &state->oif_sd.entity, OIF_JPEG_PAD,
 			MEDIA_LNK_FL_IMMUTABLE | MEDIA_LNK_FL_ENABLED);
 
-	mutex_lock(&state->lock);
-	ret = __s5c73m3_power_on(state);
-	if (ret == 0)
-		s5c73m3_get_fw_version(state);
-
-	__s5c73m3_power_off(state);
-	mutex_unlock(&state->lock);
-
-	v4l2_dbg(1, s5c73m3_dbg, sd, "%s: Booting %s (%d)\n",
-		 __func__, ret ? "failed" : "succeeded", ret);
-
 	return ret;
 }
 
@@ -1519,41 +1531,112 @@ static const struct v4l2_subdev_ops oif_subdev_ops = {
 	.video	= &s5c73m3_oif_video_ops,
 };
 
-static int s5c73m3_configure_gpios(struct s5c73m3 *state,
-				   const struct s5c73m3_platform_data *pdata)
+static int s5c73m3_configure_gpios(struct s5c73m3 *state)
+{
+	static const char * const gpio_names[] = {
+		"S5C73M3_STBY", "S5C73M3_RST"
+	};
+	struct i2c_client *c = state->i2c_client;
+	struct s5c73m3_gpio *g = state->gpio;
+	int ret, i;
+
+	for (i = 0; i < GPIO_NUM; ++i) {
+		unsigned int flags = GPIOF_DIR_OUT;
+		if (g[i].level)
+			flags |= GPIOF_INIT_HIGH;
+		ret = devm_gpio_request_one(&c->dev, g[i].gpio, flags,
+					    gpio_names[i]);
+		if (ret) {
+			v4l2_err(c, "failed to request gpio %s\n",
+				 gpio_names[i]);
+			return ret;
+		}
+	}
+	return 0;
+}
+
+static int s5c73m3_parse_gpios(struct s5c73m3 *state)
+{
+	static const char * const prop_names[] = {
+		"standby-gpios", "xshutdown-gpios",
+	};
+	struct device *dev = &state->i2c_client->dev;
+	struct device_node *node = dev->of_node;
+	int ret, i;
+
+	for (i = 0; i < GPIO_NUM; ++i) {
+		enum of_gpio_flags of_flags;
+
+		ret = of_get_named_gpio_flags(node, prop_names[i],
+					      0, &of_flags);
+		if (ret < 0) {
+			dev_err(dev, "failed to parse %s DT property\n",
+				prop_names[i]);
+			return -EINVAL;
+		}
+		state->gpio[i].gpio = ret;
+		state->gpio[i].level = !(of_flags & OF_GPIO_ACTIVE_LOW);
+	}
+	return 0;
+}
+
+static int s5c73m3_get_platform_data(struct s5c73m3 *state)
 {
 	struct device *dev = &state->i2c_client->dev;
-	const struct s5c73m3_gpio *gpio;
-	unsigned long flags;
+	const struct s5c73m3_platform_data *pdata = dev->platform_data;
+	struct device_node *node = dev->of_node;
+	struct device_node *node_ep;
+	struct v4l2_of_endpoint ep;
 	int ret;
 
-	state->gpio[STBY].gpio = -EINVAL;
-	state->gpio[RST].gpio  = -EINVAL;
+	if (!node) {
+		if (!pdata) {
+			dev_err(dev, "Platform data not specified\n");
+			return -EINVAL;
+		}
 
-	gpio = &pdata->gpio_stby;
-	if (gpio_is_valid(gpio->gpio)) {
-		flags = (gpio->level ? GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW)
-		      | GPIOF_EXPORT;
-		ret = devm_gpio_request_one(dev, gpio->gpio, flags,
-					    "S5C73M3_STBY");
-		if (ret < 0)
-			return ret;
+		state->mclk_frequency = pdata->mclk_frequency;
+		state->gpio[STBY] = pdata->gpio_stby;
+		state->gpio[RST] = pdata->gpio_reset;
+		return 0;
+	}
+
+	state->clock = devm_clk_get(dev, S5C73M3_CLK_NAME);
+	if (IS_ERR(state->clock))
+		return PTR_ERR(state->clock);
 
-		state->gpio[STBY] = *gpio;
+	if (of_property_read_u32(node, "clock-frequency",
+				 &state->mclk_frequency)) {
+		state->mclk_frequency = S5C73M3_DEFAULT_MCLK_FREQ;
+		dev_info(dev, "using default %u Hz clock frequency\n",
+					state->mclk_frequency);
 	}
 
-	gpio = &pdata->gpio_reset;
-	if (gpio_is_valid(gpio->gpio)) {
-		flags = (gpio->level ? GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW)
-		      | GPIOF_EXPORT;
-		ret = devm_gpio_request_one(dev, gpio->gpio, flags,
-					    "S5C73M3_RST");
-		if (ret < 0)
-			return ret;
+	ret = s5c73m3_parse_gpios(state);
+	if (ret < 0)
+		return -EINVAL;
 
-		state->gpio[RST] = *gpio;
+	node_ep = v4l2_of_get_next_endpoint(node, NULL);
+	if (!node_ep) {
+		dev_warn(dev, "no endpoint defined for node: %s\n",
+						node->full_name);
+		return 0;
 	}
 
+	v4l2_of_parse_endpoint(node_ep, &ep);
+	of_node_put(node_ep);
+
+	if (ep.bus_type != V4L2_MBUS_CSI2) {
+		dev_err(dev, "unsupported bus type\n");
+		return -EINVAL;
+	}
+	/*
+	 * Number of MIPI CSI-2 data lanes is currently not configurable,
+	 * always a default value of 4 lanes is used.
+	 */
+	if (ep.bus.mipi_csi2.num_data_lanes != S5C73M3_MIPI_DATA_LANES)
+		dev_info(dev, "falling back to 4 MIPI CSI-2 data lanes\n");
+
 	return 0;
 }
 
@@ -1561,21 +1644,20 @@ static int s5c73m3_probe(struct i2c_client *client,
 				const struct i2c_device_id *id)
 {
 	struct device *dev = &client->dev;
-	const struct s5c73m3_platform_data *pdata = client->dev.platform_data;
 	struct v4l2_subdev *sd;
 	struct v4l2_subdev *oif_sd;
 	struct s5c73m3 *state;
 	int ret, i;
 
-	if (pdata == NULL) {
-		dev_err(&client->dev, "Platform data not specified\n");
-		return -EINVAL;
-	}
-
 	state = devm_kzalloc(dev, sizeof(*state), GFP_KERNEL);
 	if (!state)
 		return -ENOMEM;
 
+	state->i2c_client = client;
+	ret = s5c73m3_get_platform_data(state);
+	if (ret < 0)
+		return ret;
+
 	mutex_init(&state->lock);
 	sd = &state->sensor_sd;
 	oif_sd = &state->oif_sd;
@@ -1613,11 +1695,7 @@ static int s5c73m3_probe(struct i2c_client *client,
 	if (ret < 0)
 		return ret;
 
-	state->mclk_frequency = pdata->mclk_frequency;
-	state->bus_type = pdata->bus_type;
-	state->i2c_client = client;
-
-	ret = s5c73m3_configure_gpios(state, pdata);
+	ret = s5c73m3_configure_gpios(state);
 	if (ret)
 		goto out_err;
 
@@ -1651,9 +1729,29 @@ static int s5c73m3_probe(struct i2c_client *client,
 	if (ret < 0)
 		goto out_err;
 
+	oif_sd->dev = dev;
+
+	ret = __s5c73m3_power_on(state);
+	if (ret < 0)
+		goto out_err1;
+
+	ret = s5c73m3_get_fw_version(state);
+	__s5c73m3_power_off(state);
+
+	if (ret < 0) {
+		dev_err(dev, "Device detection failed: %d\n", ret);
+		goto out_err1;
+	}
+
+	ret = v4l2_async_register_subdev(oif_sd);
+	if (ret < 0)
+		goto out_err1;
+
 	v4l2_info(sd, "%s: completed successfully\n", __func__);
 	return 0;
 
+out_err1:
+	s5c73m3_unregister_spi_driver(state);
 out_err:
 	media_entity_cleanup(&sd->entity);
 	return ret;
@@ -1665,7 +1763,7 @@ static int s5c73m3_remove(struct i2c_client *client)
 	struct s5c73m3 *state = oif_sd_to_s5c73m3(oif_sd);
 	struct v4l2_subdev *sensor_sd = &state->sensor_sd;
 
-	v4l2_device_unregister_subdev(oif_sd);
+	v4l2_async_unregister_subdev(oif_sd);
 
 	v4l2_ctrl_handler_free(oif_sd->ctrl_handler);
 	media_entity_cleanup(&oif_sd->entity);
@@ -1684,8 +1782,17 @@ static const struct i2c_device_id s5c73m3_id[] = {
 };
 MODULE_DEVICE_TABLE(i2c, s5c73m3_id);
 
+#ifdef CONFIG_OF
+static const struct of_device_id s5c73m3_of_match[] = {
+	{ .compatible = "samsung,s5c73m3" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, s5c73m3_of_match);
+#endif
+
 static struct i2c_driver s5c73m3_i2c_driver = {
 	.driver = {
+		.of_match_table = of_match_ptr(s5c73m3_of_match),
 		.name	= DRIVER_NAME,
 	},
 	.probe		= s5c73m3_probe,

drivers/media/i2c/s5c73m3/s5c73m3-spi.c

@@ -27,6 +27,11 @@
 
 #define S5C73M3_SPI_DRV_NAME "S5C73M3-SPI"
 
+static const struct of_device_id s5c73m3_spi_ids[] = {
+	{ .compatible = "samsung,s5c73m3" },
+	{ }
+};
+
 enum spi_direction {
 	SPI_DIR_RX,
 	SPI_DIR_TX
@@ -146,6 +151,7 @@ int s5c73m3_register_spi_driver(struct s5c73m3 *state)
 	spidrv->driver.name = S5C73M3_SPI_DRV_NAME;
 	spidrv->driver.bus = &spi_bus_type;
 	spidrv->driver.owner = THIS_MODULE;
+	spidrv->driver.of_match_table = s5c73m3_spi_ids;
 
 	return spi_register_driver(spidrv);
 }

drivers/media/i2c/s5c73m3/s5c73m3.h

@@ -17,6 +17,7 @@
 #ifndef S5C73M3_H_
 #define S5C73M3_H_
 
+#include <linux/clk.h>
 #include <linux/kernel.h>
 #include <linux/regulator/consumer.h>
 #include <media/v4l2-common.h>
@@ -321,6 +322,7 @@ enum s5c73m3_oif_pads {
 
 
 #define S5C73M3_MAX_SUPPLIES			6
+#define S5C73M3_DEFAULT_MCLK_FREQ		24000000U
 
 struct s5c73m3_ctrls {
 	struct v4l2_ctrl_handler handler;
@@ -391,6 +393,8 @@ struct s5c73m3 {
 	struct regulator_bulk_data supplies[S5C73M3_MAX_SUPPLIES];
 	struct s5c73m3_gpio gpio[GPIO_NUM];
 
+	struct clk *clock;
+
 	/* External master clock frequency */
 	u32 mclk_frequency;
 	/* Video bus type - MIPI-CSI2/parallel */