[v2 2/3] media: ov8856: Add devicetree support

Robert Foss
2020-03-13T11:04:15Z

Add devicetree match table, and enable ov8856_probe()
to initialize power, clocks and reset pins.

Signed-off-by: Robert Foss <robert.foss@linaro.org>
---

- Changes since v1:
* Fabio: Change n_shutdown_gpio name to reset_gpio
* Fabio: Invert reset_gpio due to GPIO_ACTIVE_HIGH -> GPIO_ACTIVE_LOW change
* Fabio: Remove empty line
* Fabio: Remove real error from devm_gpiod_get() failures
* Andy & Sakari: Make XVCLK optional since to not break ACPI
* Sakari: ARRAY_SIZE() directly instead of through OV8856_NUM_SUPPLIES
* Sakari: Use XVCLK rate as provided by DT

drivers/media/i2c/ov8856.c | 109 ++++++++++++++++++++++++++++++++++++-
1 file changed, 107 insertions(+), 2 deletions(-)

diff --git a/drivers/media/i2c/ov8856.c b/drivers/media/i2c/ov8856.c
index 8655842af275..db61eed223e8 100644
--- a/drivers/media/i2c/ov8856.c
+++ b/drivers/media/i2c/ov8856.c
@@ -3,10 +3,13 @@

#include <asm/unaligned.h>
#include <linux/acpi.h>
+#include <linux/clk.h>
#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/module.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>
@@ -19,6 +22,8 @@
#define OV8856_LINK_FREQ_180MHZ 180000000ULL
#define OV8856_SCLK 144000000ULL
#define OV8856_MCLK 19200000
+#define OV8856_XVCLK_19_2 19200000
+#define OV8856_XVCLK_24 24000000
#define OV8856_DATA_LANES 4
#define OV8856_RGB_DEPTH 10

@@ -64,6 +69,12 @@

#define to_ov8856(_sd) container_of(_sd, struct ov8856, sd)

+static const char * const ov8856_supply_names[] = {
+ "dovdd", /* Digital I/O power */
+ "avdd", /* Analog power */
+ "dvdd", /* Digital core power */
+};
+
enum {
OV8856_LINK_FREQ_720MBPS,
OV8856_LINK_FREQ_360MBPS,
@@ -566,6 +577,10 @@ struct ov8856 {
struct media_pad pad;
struct v4l2_ctrl_handler ctrl_handler;

+ struct clk *xvclk;
+ struct gpio_desc *reset_gpio;
+ struct regulator_bulk_data supplies[ARRAY_SIZE(ov8856_supply_names)];
+
/* V4L2 Controls */
struct v4l2_ctrl *link_freq;
struct v4l2_ctrl *pixel_rate;
@@ -908,6 +923,46 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable)
return ret;
}

+static int __ov8856_power_on(struct ov8856 *ov8856)
+{
+ struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
+ int ret;
+
+ ret = clk_prepare_enable(ov8856->xvclk);
+ if (ret < 0) {
+ dev_err(&client->dev, "failed to enable xvclk\n");
+ return ret;
+ }
+
+ gpiod_set_value_cansleep(ov8856->reset_gpio, GPIOD_OUT_HIGH);
+
+ ret = regulator_bulk_enable(ARRAY_SIZE(ov8856_supply_names),
+ ov8856->supplies);
+ if (ret < 0) {
+ dev_err(&client->dev, "failed to enable regulators\n");
+ goto disable_clk;
+ }
+
+ gpiod_set_value_cansleep(ov8856->reset_gpio, GPIOD_OUT_LOW);
+
+ usleep_range(1500, 1800);
+
+ return 0;
+
+disable_clk:
+ clk_disable_unprepare(ov8856->xvclk);
+
+ return ret;
+}
+
+static void __ov8856_power_off(struct ov8856 *ov8856)
+{
+ gpiod_set_value_cansleep(ov8856->reset_gpio, GPIOD_OUT_HIGH);
+ regulator_bulk_disable(ARRAY_SIZE(ov8856_supply_names),
+ ov8856->supplies);
+ clk_disable_unprepare(ov8856->xvclk);
+}
+
static int __maybe_unused ov8856_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
@@ -1175,7 +1230,7 @@ static int ov8856_remove(struct i2c_client *client)
static int ov8856_probe(struct i2c_client *client)
{
struct ov8856 *ov8856;
- int ret;
+ int i, ret;

ret = ov8856_check_hwcfg(&client->dev);
if (ret) {
@@ -1189,10 +1244,50 @@ static int ov8856_probe(struct i2c_client *client)
return -ENOMEM;

v4l2_i2c_subdev_init(&ov8856->sd, client, &ov8856_subdev_ops);
+ ov8856->xvclk = devm_clk_get(&client->dev, "xvclk");
+ if (PTR_ERR(ov8856->xvclk) == -ENOENT) {
+ dev_info(&client->dev, "xvclk clock not defined, continuing...\n");
+ ov8856->xvclk = NULL;
+ } else if (IS_ERR(ov8856->xvclk)) {
+ dev_err(&client->dev, "could not get xvclk clock (%ld)\n",
+ PTR_ERR(ov8856->xvclk));
+ return PTR_ERR(ov8856->xvclk);
+ }
+
+ ret = clk_set_rate(ov8856->xvclk, OV8856_XVCLK_24);
+ if (ret < 0) {
+ dev_err(&client->dev, "failed to set xvclk rate (24MHz)\n");
+ return ret;
+ }
+
+ ov8856->reset_gpio = devm_gpiod_get(&client->dev, "reset",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(ov8856->reset_gpio)) {
+ dev_err(&client->dev, "failed to get reset-gpios\n");
+ return PTR_ERR(ov8856->reset_gpio);
+ }
+
+ for (i = 0; i < ARRAY_SIZE(ov8856_supply_names); i++)
+ ov8856->supplies[i].supply = ov8856_supply_names[i];
+
+ ret = devm_regulator_bulk_get(&client->dev,
+ ARRAY_SIZE(ov8856_supply_names),
+ ov8856->supplies);
+ if (ret) {
+ dev_warn(&client->dev, "failed to get regulators\n");
+ return ret;
+ }
+
+ ret = __ov8856_power_on(ov8856);
+ if (ret) {
+ dev_warn(&client->dev, "failed to power on\n");
+ return ret;
+ }
+
ret = ov8856_identify_module(ov8856);
if (ret) {
dev_err(&client->dev, "failed to find sensor: %d", ret);
- return ret;
+ goto probe_power_off;
}

mutex_init(&ov8856->mutex);
@@ -1238,6 +1333,9 @@ static int ov8856_probe(struct i2c_client *client)
v4l2_ctrl_handler_free(ov8856->sd.ctrl_handler);
mutex_destroy(&ov8856->mutex);

+probe_power_off:
+ __ov8856_power_off(ov8856);
+
return ret;
}

@@ -1254,11 +1352,18 @@ static const struct acpi_device_id ov8856_acpi_ids[] = {
MODULE_DEVICE_TABLE(acpi, ov8856_acpi_ids);
#endif

+static const struct of_device_id ov8856_of_match[] = {
+ { .compatible = "ovti,ov8856" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, ov8856_of_match);
+
static struct i2c_driver ov8856_i2c_driver = {
.driver = {
.name = "ov8856",
.pm = &ov8856_pm_ops,
.acpi_match_table = ACPI_PTR(ov8856_acpi_ids),
+ .of_match_table = ov8856_of_match,
},
.probe_new = ov8856_probe,
.remove = ov8856_remove,
--
2.20.1