media: ov08x40: Add OF probe support

The ACPI version of this driver "just works" on dts based systems with a
few extensions to facilitate.

- Add support for DT based probing
- Add support for taking the part out of reset via a GPIO reset pin
- Add in regulator bulk on/off logic for the power rails.

Once done this sensor works nicely on a Qualcomm X1E80100 CRD.

Tested-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org> # x1e80100-crd
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>

diff --git a/drivers/media/i2c/ov08x40.c b/drivers/media/i2c/ov08x40.c
index 3ab8b51df157af78fcccc1aaef73aedb2ae759c9..ff17e09a1f96175d598c395bcae0cdf01d68a79f 100644 (file)
--- a/drivers/media/i2c/ov08x40.c
+++ b/drivers/media/i2c/ov08x40.c
@@ -3,10 +3,13 @@
 
 #include <asm-generic/unaligned.h>
 #include <linux/acpi.h>
+#include <linux/clk.h>
 #include <linux/i2c.h>
+#include <linux/gpio/consumer.h>
 #include <linux/module.h>
 #include <linux/delay.h>
 #include <linux/pm_runtime.h>
+#include <linux/regulator/consumer.h>
 #include <media/v4l2-ctrls.h>
 #include <media/v4l2-device.h>
 #include <media/v4l2-fwnode.h>
@@ -1279,6 +1282,12 @@ static const struct ov08x40_mode supported_modes[] = {
        },
 };
 
+static const char * const ov08x40_supply_names[] = {
+       "dovdd",        /* Digital I/O power */
+       "avdd",         /* Analog power */
+       "dvdd",         /* Digital core power */
+};
+
 struct ov08x40 {
        struct v4l2_subdev sd;
        struct media_pad pad;
@@ -1291,6 +1300,10 @@ struct ov08x40 {
        struct v4l2_ctrl *hblank;
        struct v4l2_ctrl *exposure;
 
+       struct clk              *xvclk;
+       struct gpio_desc        *reset_gpio;
+       struct regulator_bulk_data supplies[ARRAY_SIZE(ov08x40_supply_names)];
+
        /* Current mode */
        const struct ov08x40_mode *cur_mode;
 
@@ -1303,6 +1316,61 @@ struct ov08x40 {
 
 #define to_ov08x40(_sd)        container_of(_sd, struct ov08x40, sd)
 
+static int ov08x40_power_on(struct device *dev)
+{
+       struct v4l2_subdev *sd = dev_get_drvdata(dev);
+       struct ov08x40 *ov08x = to_ov08x40(sd);
+       int ret;
+
+       if (is_acpi_node(dev_fwnode(dev)))
+               return 0;
+
+       ret = clk_prepare_enable(ov08x->xvclk);
+       if (ret < 0) {
+               dev_err(dev, "failed to enable xvclk\n");
+               return ret;
+       }
+
+       if (ov08x->reset_gpio) {
+               gpiod_set_value_cansleep(ov08x->reset_gpio, 1);
+               usleep_range(1000, 2000);
+       }
+
+       ret = regulator_bulk_enable(ARRAY_SIZE(ov08x40_supply_names),
+                                   ov08x->supplies);
+       if (ret < 0) {
+               dev_err(dev, "failed to enable regulators\n");
+               goto disable_clk;
+       }
+
+       gpiod_set_value_cansleep(ov08x->reset_gpio, 0);
+       usleep_range(1500, 1800);
+
+       return 0;
+
+disable_clk:
+       gpiod_set_value_cansleep(ov08x->reset_gpio, 1);
+       clk_disable_unprepare(ov08x->xvclk);
+
+       return ret;
+}
+
+static int ov08x40_power_off(struct device *dev)
+{
+       struct v4l2_subdev *sd = dev_get_drvdata(dev);
+       struct ov08x40 *ov08x = to_ov08x40(sd);
+
+       if (is_acpi_node(dev_fwnode(dev)))
+               return 0;
+
+       gpiod_set_value_cansleep(ov08x->reset_gpio, 1);
+       regulator_bulk_disable(ARRAY_SIZE(ov08x40_supply_names),
+                              ov08x->supplies);
+       clk_disable_unprepare(ov08x->xvclk);
+
+       return 0;
+}
+
 /* Read registers up to 4 at a time */
 static int ov08x40_read_reg(struct ov08x40 *ov08x,
                            u16 reg, u32 len, u32 *val)
@@ -2072,7 +2140,7 @@ static void ov08x40_free_controls(struct ov08x40 *ov08x)
        mutex_destroy(&ov08x->mutex);
 }
 
-static int ov08x40_check_hwcfg(struct device *dev)
+static int ov08x40_check_hwcfg(struct ov08x40 *ov08x, struct device *dev)
 {
        struct v4l2_fwnode_endpoint bus_cfg = {
                .bus_type = V4L2_MBUS_CSI2_DPHY
@@ -2086,11 +2154,36 @@ static int ov08x40_check_hwcfg(struct device *dev)
        if (!fwnode)
                return -ENXIO;
 
-       ret = fwnode_property_read_u32(dev_fwnode(dev), "clock-frequency",
-                                      &xvclk_rate);
-       if (ret) {
-               dev_err(dev, "can't get clock frequency");
-               return ret;
+       if (!is_acpi_node(fwnode)) {
+               ov08x->xvclk = devm_clk_get(dev, NULL);
+               if (IS_ERR(ov08x->xvclk)) {
+                       dev_err(dev, "could not get xvclk clock (%pe)\n",
+                               ov08x->xvclk);
+                       return PTR_ERR(ov08x->xvclk);
+               }
+
+               xvclk_rate = clk_get_rate(ov08x->xvclk);
+
+               ov08x->reset_gpio = devm_gpiod_get_optional(dev, "reset",
+                                                           GPIOD_OUT_LOW);
+               if (IS_ERR(ov08x->reset_gpio))
+                       return PTR_ERR(ov08x->reset_gpio);
+
+               for (i = 0; i < ARRAY_SIZE(ov08x40_supply_names); i++)
+                       ov08x->supplies[i].supply = ov08x40_supply_names[i];
+
+               ret = devm_regulator_bulk_get(dev,
+                                             ARRAY_SIZE(ov08x40_supply_names),
+                                             ov08x->supplies);
+               if (ret)
+                       return ret;
+       } else {
+               ret = fwnode_property_read_u32(dev_fwnode(dev), "clock-frequency",
+                                              &xvclk_rate);
+               if (ret) {
+                       dev_err(dev, "can't get clock frequency");
+                       return ret;
+               }
        }
 
        if (xvclk_rate != OV08X40_XVCLK) {
@@ -2143,32 +2236,37 @@ out_err:
 }
 
 static int ov08x40_probe(struct i2c_client *client)
-{
-       struct ov08x40 *ov08x;
+{      struct ov08x40 *ov08x;
        int ret;
        bool full_power;
 
+       ov08x = devm_kzalloc(&client->dev, sizeof(*ov08x), GFP_KERNEL);
+       if (!ov08x)
+               return -ENOMEM;
+
        /* Check HW config */
-       ret = ov08x40_check_hwcfg(&client->dev);
+       ret = ov08x40_check_hwcfg(ov08x, &client->dev);
        if (ret) {
                dev_err(&client->dev, "failed to check hwcfg: %d", ret);
                return ret;
        }
 
-       ov08x = devm_kzalloc(&client->dev, sizeof(*ov08x), GFP_KERNEL);
-       if (!ov08x)
-               return -ENOMEM;
-
        /* Initialize subdev */
        v4l2_i2c_subdev_init(&ov08x->sd, client, &ov08x40_subdev_ops);
 
        full_power = acpi_dev_state_d0(&client->dev);
        if (full_power) {
+               ret = ov08x40_power_on(&client->dev);
+               if (ret) {
+                       dev_err(&client->dev, "failed to power on\n");
+                       return ret;
+               }
+
                /* Check module identity */
                ret = ov08x40_identify_module(ov08x);
                if (ret) {
                        dev_err(&client->dev, "failed to find sensor: %d\n", ret);
-                       return ret;
+                       goto probe_power_off;
                }
        }
 
@@ -2177,7 +2275,7 @@ static int ov08x40_probe(struct i2c_client *client)
 
        ret = ov08x40_init_controls(ov08x);
        if (ret)
-               return ret;
+               goto probe_power_off;
 
        /* Initialize subdev */
        ov08x->sd.internal_ops = &ov08x40_internal_ops;
@@ -2210,6 +2308,9 @@ error_media_entity:
 error_handler_free:
        ov08x40_free_controls(ov08x);
 
+probe_power_off:
+       ov08x40_power_off(&client->dev);
+
        return ret;
 }
 
@@ -2224,6 +2325,8 @@ static void ov08x40_remove(struct i2c_client *client)
 
        pm_runtime_disable(&client->dev);
        pm_runtime_set_suspended(&client->dev);
+
+       ov08x40_power_off(&client->dev);
 }
 
 #ifdef CONFIG_ACPI
@@ -2235,10 +2338,17 @@ static const struct acpi_device_id ov08x40_acpi_ids[] = {
 MODULE_DEVICE_TABLE(acpi, ov08x40_acpi_ids);
 #endif
 
+static const struct of_device_id ov08x40_of_match[] = {
+       { .compatible = "ovti,ov08x40" },
+       { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, ov08x40_of_match);
+
 static struct i2c_driver ov08x40_i2c_driver = {
        .driver = {
                .name = "ov08x40",
                .acpi_match_table = ACPI_PTR(ov08x40_acpi_ids),
+               .of_match_table = ov08x40_of_match,
        },
        .probe = ov08x40_probe,
        .remove = ov08x40_remove,