Hi Quentin,
one more question
On Wed, May 25, 2022 at 04:58:31PM +0200, Quentin Schulz wrote:
> From: Quentin Schulz <quentin.schulz@xxxxxxxxxxxxxxxxxxxxx>
>
> Until now, this driver only supported ACPI. This adds support for
> Device Tree too while enabling clock and regulators in runtime PM.
>
> Signed-off-by: Quentin Schulz <quentin.schulz@xxxxxxxxxxxxxxxxxxxxx>
> ---
>
> v5:
> - fixed -Wdeclaration-after-statement for delay_us,
>
> v4:
> - added delays based on clock cycles as specified in datasheet for
> pre-power-off and post-power-on,
> - re-arranged clk handling, shutdown toggling and regulator handling to
> better match power up/down sequence defined in datasheet,
> - added comment on need for regulator being stable before releasing
> shutdown pin,
>
> v3:
> - added linux/mod_devicetable.h include,
> - moved delay for reset pulse right after the regulators are enabled,
> - removed check on is_acpi_node in favor of checks on presence of OF
> properties (e.g. devm_clk_get_optional returns NULL),
> - moved power management out of system suspend/resume into runtime PM
> callbacks,
> - removed ACPI specific comment since it's not specific to this driver,
> - changed devm_clk_get to devm_clk_get_optional,
> - remove OF use of clock-frequency (handled by devm_clk_get_optional
> directly),
> - removed name of clock (only one, so no need for anything explicit)
> when requesting a clock from OF,
> - wrapped lines to 80 chars,
>
> v2:
> - fixed unused-const-variable warning by removing of_match_ptr in
> of_match_table, reported by kernel test robot,
>
> drivers/media/i2c/ov5675.c | 149 +++++++++++++++++++++++++++++++------
> 1 file changed, 128 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/media/i2c/ov5675.c b/drivers/media/i2c/ov5675.c
> index 82ba9f56baec8..ea801edb8e408 100644
> --- a/drivers/media/i2c/ov5675.c
> +++ b/drivers/media/i2c/ov5675.c
> @@ -3,10 +3,14 @@
>
> #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/mod_devicetable.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>
> @@ -17,7 +21,7 @@
>
> #define OV5675_LINK_FREQ_450MHZ 450000000ULL
> #define OV5675_SCLK 90000000LL
> -#define OV5675_MCLK 19200000
> +#define OV5675_XVCLK_19_2 19200000
> #define OV5675_DATA_LANES 2
> #define OV5675_RGB_DEPTH 10
>
> @@ -76,6 +80,14 @@
>
> #define to_ov5675(_sd) container_of(_sd, struct ov5675, sd)
>
> +static const char * const ov5675_supply_names[] = {
> + "avdd", /* Analog power */
> + "dovdd", /* Digital I/O power */
> + "dvdd", /* Digital core power */
> +};
> +
> +#define OV5675_NUM_SUPPLIES ARRAY_SIZE(ov5675_supply_names)
> +
> enum {
> OV5675_LINK_FREQ_900MBPS,
> };
> @@ -484,6 +496,9 @@ struct ov5675 {
> struct v4l2_subdev sd;
> struct media_pad pad;
> struct v4l2_ctrl_handler ctrl_handler;
> + struct clk *xvclk;
> + struct gpio_desc *reset_gpio;
> + struct regulator_bulk_data supplies[OV5675_NUM_SUPPLIES];
>
> /* V4L2 Controls */
> struct v4l2_ctrl *link_freq;
> @@ -944,6 +959,56 @@ static int ov5675_set_stream(struct v4l2_subdev *sd, int enable)
> return ret;
> }
>
> +static int ov5675_power_off(struct device *dev)
Does this (and power_on) require __maybe_unused to avoid a warning
when compiling without CONFIG_PM support ? Have you tried that ?
Thanks
j
> +{
> + struct v4l2_subdev *sd = dev_get_drvdata(dev);
> + struct ov5675 *ov5675 = to_ov5675(sd);
> + /* 512 xvclk cycles after the last SCCB transation or MIPI frame end */
> + u32 delay_us = DIV_ROUND_UP(512, OV5675_XVCLK_19_2 / 1000 / 1000);
> +
> + usleep_range(delay_us, delay_us * 2);
> +
> + clk_disable_unprepare(ov5675->xvclk);
> + gpiod_set_value_cansleep(ov5675->reset_gpio, 1);
> + regulator_bulk_disable(OV5675_NUM_SUPPLIES, ov5675->supplies);
> +
> + return 0;
> +}
> +
> +static int ov5675_power_on(struct device *dev)
> +{
> + struct v4l2_subdev *sd = dev_get_drvdata(dev);
> + struct ov5675 *ov5675 = to_ov5675(sd);
> + u32 delay_us = DIV_ROUND_UP(8192, OV5675_XVCLK_19_2 / 1000 / 1000);
> + int ret;
> +
> + ret = clk_prepare_enable(ov5675->xvclk);
> + if (ret < 0) {
> + dev_err(dev, "failed to enable xvclk: %d\n", ret);
> + return ret;
> + }
> +
> + gpiod_set_value_cansleep(ov5675->reset_gpio, 1);
> +
> + ret = regulator_bulk_enable(OV5675_NUM_SUPPLIES, ov5675->supplies);
> + if (ret) {
> + clk_disable_unprepare(ov5675->xvclk);
> + return ret;
> + }
> +
> + /* Reset pulse should be at least 2ms and reset gpio released only once
> + * regulators are stable.
> + */
> + usleep_range(2000, 2200);
> +
> + gpiod_set_value_cansleep(ov5675->reset_gpio, 0);
> +
> + /* 8192 xvclk cycles prior to the first SCCB transation */
> + usleep_range(delay_us, delay_us * 2);
> +
> + return 0;
> +}
> +
> static int __maybe_unused ov5675_suspend(struct device *dev)
> {
> struct v4l2_subdev *sd = dev_get_drvdata(dev);
> @@ -1106,32 +1171,60 @@ static const struct v4l2_subdev_internal_ops ov5675_internal_ops = {
> .open = ov5675_open,
> };
>
> -static int ov5675_check_hwcfg(struct device *dev)
> +static int ov5675_get_hwcfg(struct ov5675 *ov5675, struct device *dev)
> {
> struct fwnode_handle *ep;
> struct fwnode_handle *fwnode = dev_fwnode(dev);
> struct v4l2_fwnode_endpoint bus_cfg = {
> .bus_type = V4L2_MBUS_CSI2_DPHY
> };
> - u32 mclk;
> + u32 xvclk_rate;
> int ret;
> unsigned int i, j;
>
> if (!fwnode)
> return -ENXIO;
>
> - ret = fwnode_property_read_u32(fwnode, "clock-frequency", &mclk);
> + ov5675->xvclk = devm_clk_get_optional(dev, NULL);
> + if (IS_ERR(ov5675->xvclk))
> + return dev_err_probe(dev, PTR_ERR(ov5675->xvclk),
> + "failed to get xvclk: %ld\n",
> + PTR_ERR(ov5675->xvclk));
>
> - if (ret) {
> - dev_err(dev, "can't get clock frequency");
> - return ret;
> + if (ov5675->xvclk) {
> + xvclk_rate = clk_get_rate(ov5675->xvclk);
> + } else {
> + ret = fwnode_property_read_u32(fwnode, "clock-frequency",
> + &xvclk_rate);
> +
> + if (ret) {
> + dev_err(dev, "can't get clock frequency");
> + return ret;
> + }
> }
>
> - if (mclk != OV5675_MCLK) {
> - dev_err(dev, "external clock %d is not supported", mclk);
> + if (xvclk_rate != OV5675_XVCLK_19_2) {
> + dev_err(dev, "external clock rate %u is unsupported",
> + xvclk_rate);
> return -EINVAL;
> }
>
> + ov5675->reset_gpio = devm_gpiod_get_optional(dev, "reset",
> + GPIOD_OUT_HIGH);
> + if (IS_ERR(ov5675->reset_gpio)) {
> + ret = PTR_ERR(ov5675->reset_gpio);
> + dev_err(dev, "failed to get reset-gpios: %d\n", ret);
> + return ret;
> + }
> +
> + for (i = 0; i < OV5675_NUM_SUPPLIES; i++)
> + ov5675->supplies[i].supply = ov5675_supply_names[i];
> +
> + ret = devm_regulator_bulk_get(dev, OV5675_NUM_SUPPLIES,
> + ov5675->supplies);
> + if (ret)
> + return ret;
> +
> ep = fwnode_graph_get_next_endpoint(fwnode, NULL);
> if (!ep)
> return -ENXIO;
> @@ -1186,6 +1279,9 @@ static int ov5675_remove(struct i2c_client *client)
> pm_runtime_disable(&client->dev);
> mutex_destroy(&ov5675->mutex);
>
> + if (!pm_runtime_status_suspended(&client->dev))
> + ov5675_power_off(&client->dev);
> +
> return 0;
> }
>
> @@ -1195,25 +1291,31 @@ static int ov5675_probe(struct i2c_client *client)
> bool full_power;
> int ret;
>
> - ret = ov5675_check_hwcfg(&client->dev);
> + ov5675 = devm_kzalloc(&client->dev, sizeof(*ov5675), GFP_KERNEL);
> + if (!ov5675)
> + return -ENOMEM;
> +
> + ret = ov5675_get_hwcfg(ov5675, &client->dev);
> if (ret) {
> - dev_err(&client->dev, "failed to check HW configuration: %d",
> + dev_err(&client->dev, "failed to get HW configuration: %d",
> ret);
> return ret;
> }
>
> - ov5675 = devm_kzalloc(&client->dev, sizeof(*ov5675), GFP_KERNEL);
> - if (!ov5675)
> - return -ENOMEM;
> -
> v4l2_i2c_subdev_init(&ov5675->sd, client, &ov5675_subdev_ops);
>
> + ret = ov5675_power_on(&client->dev);
> + if (ret) {
> + dev_err(&client->dev, "failed to power on: %d\n", ret);
> + return ret;
> + }
> +
> full_power = acpi_dev_state_d0(&client->dev);
> if (full_power) {
> ret = ov5675_identify_module(ov5675);
> if (ret) {
> dev_err(&client->dev, "failed to find sensor: %d", ret);
> - return ret;
> + goto probe_power_off;
> }
> }
>
> @@ -1243,11 +1345,6 @@ static int ov5675_probe(struct i2c_client *client)
> goto probe_error_media_entity_cleanup;
> }
>
> - /*
> - * Device is already turned on by i2c-core with ACPI domain PM.
> - * Enable runtime PM and turn off the device.
> - */
> -
> /* Set the device's state to active if it's in D0 state. */
> if (full_power)
> pm_runtime_set_active(&client->dev);
> @@ -1262,12 +1359,15 @@ static int ov5675_probe(struct i2c_client *client)
> probe_error_v4l2_ctrl_handler_free:
> v4l2_ctrl_handler_free(ov5675->sd.ctrl_handler);
> mutex_destroy(&ov5675->mutex);
> +probe_power_off:
> + ov5675_power_off(&client->dev);
>
> return ret;
> }
>
> static const struct dev_pm_ops ov5675_pm_ops = {
> SET_SYSTEM_SLEEP_PM_OPS(ov5675_suspend, ov5675_resume)
> + SET_RUNTIME_PM_OPS(ov5675_power_off, ov5675_power_on, NULL)
> };
>
> #ifdef CONFIG_ACPI
> @@ -1279,11 +1379,18 @@ static const struct acpi_device_id ov5675_acpi_ids[] = {
> MODULE_DEVICE_TABLE(acpi, ov5675_acpi_ids);
> #endif
>
> +static const struct of_device_id ov5675_of_match[] = {
> + { .compatible = "ovti,ov5675", },
> + { /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, ov5675_of_match);
> +
> static struct i2c_driver ov5675_i2c_driver = {
> .driver = {
> .name = "ov5675",
> .pm = &ov5675_pm_ops,
> .acpi_match_table = ACPI_PTR(ov5675_acpi_ids),
> + .of_match_table = ov5675_of_match,
> },
> .probe_new = ov5675_probe,
> .remove = ov5675_remove,
> --
> 2.36.1
>
