Hi Mehdi,
This is starting to look good! See more comments below.
On Wed 08 Nov 23, 14:27, Mehdi Djait wrote:
> The Techwell video decoder supports PAL, NTSC standards and
> has a parallel BT.656 output interface.
>
> This commit adds support for this device, with basic support
> for NTSC and PAL, along with brightness and contrast controls.
>
> The TW9900 is capable of automatic standard detection. This
> driver is implemented with support for PAL and NTSC
> autodetection.
>
> Signed-off-by: Mehdi Djait <[email protected]>
> ---
> V7->V8:
> - added a mutex to Serialize access to hardware and current mode configuration
> - added back pm_runtime
> - split get_fmt and set_fmt callbacks
> - removed the tw9900_cancel_autodetect()
>
> V6->V7:
> - added #include <linux/bitfield.h> to fix a Warning from the kernel
> robot
> - removed a dev_info and replaced a dev_err by dev_err_probe
>
> V5->V6:
> - dropped .skip_top and .field in the supported_modes
> - added error handling for the i2c writes/reads
> - added the colorimetry information to fill_fmt
> - removed pm_runtime
> - added the g_input_status callback
> - dropped SECAM
> - dropped the non-standard PAL/NTSC variants
>
> V4->V5:
> - Added .querystd() and .g_tvnorms(), dropped the .open() and
> unified the g_fmt() / s_fmt().
>
> V3->V4:
> - Fix a warning about an uninitialized ret variable in probe()
>
> V2->V3:
> - Fix coding-style issues, and remove the use of the bulk API
> for regulators. Make the driver select the media-controller and
> V4L2-subdev APIs.
>
> V1->V2:
> - Set the media entity type to decoder, and implement the
> s_std/g_std ops
>
> MAINTAINERS | 6 +
> drivers/media/i2c/Kconfig | 12 +
> drivers/media/i2c/Makefile | 1 +
> drivers/media/i2c/tw9900.c | 771 +++++++++++++++++++++++++++++++++++++
> 4 files changed, 790 insertions(+)
> create mode 100644 drivers/media/i2c/tw9900.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 3b47e0b56859..c2e69b642609 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -21142,6 +21142,12 @@ L: [email protected]
> S: Maintained
> F: drivers/media/rc/ttusbir.c
>
> +TECHWELL TW9900 VIDEO DECODER
> +M: Mehdi Djait <[email protected]>
> +L: [email protected]
> +S: Maintained
> +F: drivers/media/i2c/tw9900.c
> +
> TECHWELL TW9910 VIDEO DECODER
> L: [email protected]
> S: Orphan
> diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> index 59ee0ca2c978..a9667428936e 100644
> --- a/drivers/media/i2c/Kconfig
> +++ b/drivers/media/i2c/Kconfig
> @@ -1186,6 +1186,18 @@ config VIDEO_TW2804
> To compile this driver as a module, choose M here: the
> module will be called tw2804.
>
> +config VIDEO_TW9900
> + tristate "Techwell TW9900 video decoder"
> + depends on VIDEO_DEV && I2C
You should also depend on PM and probably on GPIOLIB too.
> + select MEDIA_CONTROLLER
> + select VIDEO_V4L2_SUBDEV_API
Also select V4L2_ASYNC.
> + help
> + Support for the Techwell tw9900 multi-standard video decoder.
Uppercase "TW9900" here.
> + It supports NTSC, PAL standards with auto-detection features.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called tw9900.
> +
> config VIDEO_TW9903
> tristate "Techwell TW9903 video decoder"
> depends on VIDEO_DEV && I2C
> diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> index f5010f80a21f..a17ee899a859 100644
> --- a/drivers/media/i2c/Makefile
> +++ b/drivers/media/i2c/Makefile
> @@ -136,6 +136,7 @@ obj-$(CONFIG_VIDEO_TVP514X) += tvp514x.o
> obj-$(CONFIG_VIDEO_TVP5150) += tvp5150.o
> obj-$(CONFIG_VIDEO_TVP7002) += tvp7002.o
> obj-$(CONFIG_VIDEO_TW2804) += tw2804.o
> +obj-$(CONFIG_VIDEO_TW9900) += tw9900.o
> obj-$(CONFIG_VIDEO_TW9903) += tw9903.o
> obj-$(CONFIG_VIDEO_TW9906) += tw9906.o
> obj-$(CONFIG_VIDEO_TW9910) += tw9910.o
> diff --git a/drivers/media/i2c/tw9900.c b/drivers/media/i2c/tw9900.c
> new file mode 100644
> index 000000000000..6aa585da0864
> --- /dev/null
> +++ b/drivers/media/i2c/tw9900.c
> @@ -0,0 +1,771 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for the Techwell TW9900 multi-standard video decoder.
> + *
> + * Copyright (C) 2018 Fuzhou Rockchip Electronics Co., Ltd.
> + * Copyright (C) 2020 Maxime Chevallier <[email protected]>
> + * Copyright (C) 2023 Mehdi Djait <[email protected]>
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/clk.h>
> +#include <linux/device.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 <linux/sysfs.h>
> +#include <linux/timer.h>
Not sure timer and sysfs are needed here.
> +#include <linux/delay.h>
> +#include <media/media-entity.h>
> +#include <media/v4l2-async.h>
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-event.h>
> +#include <media/v4l2-subdev.h>
> +
> +#define TW9900_REG_CHIP_ID 0x00
> +#define TW9900_REG_CHIP_STATUS 0x01
> +#define TW9900_REG_CHIP_STATUS_VDLOSS BIT(7)
> +#define TW9900_REG_CHIP_STATUS_HLOCK BIT(6)
> +#define TW9900_REG_OUT_FMT_CTL 0x03
> +#define TW9900_REG_OUT_FMT_CTL_STANDBY 0xA7
> +#define TW9900_REG_OUT_FMT_CTL_STREAMING 0xA0
> +#define TW9900_REG_CKHY_HSDLY 0x04
> +#define TW9900_REG_OUT_CTRL_I 0x05
> +#define TW9900_REG_ANALOG_CTL 0x06
> +#define TW9900_REG_CROP_HI 0x07
> +#define TW9900_REG_VDELAY_LO 0x08
> +#define TW9900_REG_VACTIVE_LO 0x09
> +#define TW9900_REG_HACTIVE_LO 0x0B
> +#define TW9900_REG_CNTRL1 0x0C
> +#define TW9900_REG_BRIGHT_CTL 0x10
> +#define TW9900_REG_CONTRAST_CTL 0x11
> +#define TW9900_REG_VBI_CNTL 0x19
> +#define TW9900_REG_ANAL_CTL_II 0x1A
> +#define TW9900_REG_OUT_CTRL_II 0x1B
> +#define TW9900_REG_STD_SEL 0x1C
This register covers both selection and detection so it would be better called
TW9900_REG_STD. The docs call it "SDT" but that's a really bad decision.
> +#define TW9900_REG_STD_SEL_AUTODETECT_IN_PROGRESS BIT(7)
And this one is a bit long without a good reason. You could call it:
TW9900_REG_STD_AUTO_PROGRESS
And please tab-align all the defines to the longest one (or don't tab-align
at all, but keep it consistent).
> +#define TW9900_STDNOW_MASK GENMASK(6, 4)
> +#define TW9900_REG_STDR 0x1D
> +#define TW9900_REG_MISSCNT 0x26
> +#define TW9900_REG_MISC_CTL_II 0x2F
> +#define TW9900_REG_VVBI 0x55
> +
> +#define TW9900_CHIP_ID 0x00
> +
> +#define VSYNC_POLL_INTERVAL_MS 20
> +#define VSYNC_WAIT_MAX_POLLS 50
> +
> +#define TW9900_STD_NTSC_M 0
> +#define TW9900_STD_PAL_BDGHI 1
> +#define TW9900_STD_AUTO 7
> +
> +#define TW9900_VIDEO_POLL_TRIES 20
Same comment about tab-alignment.
> +
> +struct regval {
> + u8 addr;
> + u8 val;
> +};
> +
> +struct tw9900_mode {
> + u32 width;
> + u32 height;
> + u32 std;
> + const struct regval *reg_list;
> + int n_regs;
> +};
> +
> +struct tw9900 {
> + struct i2c_client *client;
> + struct gpio_desc *reset_gpio;
> + struct regulator *regulator;
> +
> + bool streaming;
This one should also be covered by the mutex. It's global state that needs
to be kept consistent across multiple users.
> +
> + struct v4l2_subdev subdev;
> + struct v4l2_ctrl_handler hdl;
> + struct media_pad pad;
> +
> + /* Serialize access to hardware and current mode configuration. */
You can mention "global state" instead of "current mode configuration".
> + struct mutex mutex;
> +
> + const struct tw9900_mode *cur_mode;
> +};
> +
> +#define to_tw9900(sd) container_of(sd, struct tw9900, subdev)
> +
> +static const struct regval tw9900_init_regs[] = {
> + { TW9900_REG_MISC_CTL_II, 0xE6 },
> + { TW9900_REG_MISSCNT, 0x24 },
> + { TW9900_REG_OUT_FMT_CTL, 0xA7 },
> + { TW9900_REG_ANAL_CTL_II, 0x0A },
> + { TW9900_REG_VDELAY_LO, 0x19 },
> + { TW9900_REG_STD_SEL, 0x00 },
> + { TW9900_REG_VACTIVE_LO, 0xF0 },
> + { TW9900_REG_STD_SEL, 0x07 },
> + { TW9900_REG_CKHY_HSDLY, 0x00 },
> + { TW9900_REG_ANALOG_CTL, 0x80 },
> + { TW9900_REG_CNTRL1, 0xDC },
> + { TW9900_REG_OUT_CTRL_I, 0x98 },
> +};
> +
> +static const struct regval tw9900_pal_regs[] = {
> + { TW9900_REG_STD_SEL, 0x01 },
> +};
> +
> +static const struct regval tw9900_ntsc_regs[] = {
> + { TW9900_REG_OUT_FMT_CTL, 0xA4 },
> + { TW9900_REG_VDELAY_LO, 0x12 },
> + { TW9900_REG_VACTIVE_LO, 0xF0 },
> + { TW9900_REG_CROP_HI, 0x02 },
> + { TW9900_REG_HACTIVE_LO, 0xD0 },
> + { TW9900_REG_VBI_CNTL, 0x01 },
> + { TW9900_REG_STD_SEL, 0x00 },
> +};
> +
> +static const struct tw9900_mode supported_modes[] = {
> + {
> + .width = 720,
> + .height = 480,
> + .std = V4L2_STD_NTSC,
> + .reg_list = tw9900_ntsc_regs,
> + .n_regs = ARRAY_SIZE(tw9900_ntsc_regs),
> + },
> + {
> + .width = 720,
> + .height = 576,
> + .std = V4L2_STD_PAL,
> + .reg_list = tw9900_pal_regs,
> + .n_regs = ARRAY_SIZE(tw9900_pal_regs),
> + },
> +};
> +
> +static int tw9900_write_reg(struct i2c_client *client, u8 reg, u8 val)
> +{
> + int ret;
> +
> + ret = i2c_smbus_write_byte_data(client, reg, val);
> + if (ret < 0)
> + dev_err(&client->dev, "write reg error: %d\n", ret);
> +
> + return ret;
> +}
> +
> +static int tw9900_write_array(struct i2c_client *client,
> + const struct regval *regs, int n_regs)
> +{
> + int i, ret = 0;
> +
> + for (i = 0; i < n_regs; i++) {
> + ret = tw9900_write_reg(client, regs[i].addr, regs[i].val);
> + if (ret)
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int tw9900_read_reg(struct i2c_client *client, u8 reg)
> +{
> + int ret;
> +
> + ret = i2c_smbus_read_byte_data(client, reg);
> + if (ret < 0)
> + dev_err(&client->dev, "read reg error: %d\n", ret);
> +
> + return ret;
> +}
> +
> +static void tw9900_fill_fmt(const struct tw9900_mode *mode,
> + struct v4l2_mbus_framefmt *fmt)
> +{
> + fmt->code = MEDIA_BUS_FMT_UYVY8_2X8;
> + fmt->width = mode->width;
> + fmt->height = mode->height;
> + fmt->field = V4L2_FIELD_NONE;
> + fmt->quantization = V4L2_QUANTIZATION_DEFAULT;
> + fmt->colorspace = V4L2_COLORSPACE_SMPTE170M;
> + fmt->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(V4L2_COLORSPACE_SMPTE170M);
> + fmt->ycbcr_enc = V4L2_MAP_YCBCR_ENC_DEFAULT(V4L2_COLORSPACE_SMPTE170M);
> +}
> +
> +static int tw9900_get_fmt(struct v4l2_subdev *sd,
> + struct v4l2_subdev_state *sd_state,
> + struct v4l2_subdev_format *fmt)
> +{
> + struct tw9900 *tw9900 = to_tw9900(sd);
> + struct v4l2_mbus_framefmt *mbus_fmt = &fmt->format;
> +
> + mutex_lock(&tw9900->mutex);
> + tw9900_fill_fmt(tw9900->cur_mode, mbus_fmt);
> + mutex_unlock(&tw9900->mutex);
> +
> + return 0;
> +}
> +
> +static int tw9900_set_fmt(struct v4l2_subdev *sd,
> + struct v4l2_subdev_state *sd_state,
> + struct v4l2_subdev_format *fmt)
> +{
> + struct tw9900 *tw9900 = to_tw9900(sd);
> +
> + if (tw9900->streaming)
> + return -EBUSY;
You need this check to be mutex-protected (so you should probably call
tw9900_fill_fmt locked directly here).
> +
> + return tw9900_get_fmt(sd, sd_state, fmt);
> +}
> +
> +static int tw9900_enum_mbus_code(struct v4l2_subdev *sd,
> + struct v4l2_subdev_state *sd_state,
> + struct v4l2_subdev_mbus_code_enum *code)
> +{
> + if (code->index > 0)
> + return -EINVAL;
> +
> + code->code = MEDIA_BUS_FMT_UYVY8_2X8;
> +
> + return 0;
> +}
> +
> +static int tw9900_power_on(struct tw9900 *tw9900)
Move this to the resume rpm handler directly. No need to have a separate
function.
> +{
> + int ret;
> +
> + if (tw9900->reset_gpio)
> + gpiod_set_value_cansleep(tw9900->reset_gpio, 1);
> +
> + ret = regulator_enable(tw9900->regulator);
> + if (ret < 0)
> + return ret;
> +
> + usleep_range(50000, 52000);
> +
> + if (tw9900->reset_gpio)
> + gpiod_set_value_cansleep(tw9900->reset_gpio, 0);
> +
> + usleep_range(1000, 2000);
> +
> + mutex_lock(&tw9900->mutex);
The mutex should apply to every operation done in this function (i.e. lock and
unlock should be the first and last things done) since it deals with global
hardware state.
> + ret = tw9900_write_array(tw9900->client, tw9900_init_regs,
> + ARRAY_SIZE(tw9900_init_regs));
> + mutex_unlock(&tw9900->mutex);
> +
> + /* This sleep is needed for the Horizontal Sync PLL to lock. */
> + msleep(300);
> +
> + return ret;
> +}
> +
> +static void tw9900_power_off(struct tw9900 *tw9900)
> +{
Same comment about folding into rpm suspend and mutex protection.
> + if (tw9900->reset_gpio)
> + gpiod_set_value_cansleep(tw9900->reset_gpio, 1);
> +
> + regulator_disable(tw9900->regulator);
> +}
> +
> +static int tw9900_s_ctrl(struct v4l2_ctrl *ctrl)
> +{
> + struct tw9900 *tw9900 = container_of(ctrl->handler, struct tw9900, hdl);
> + int ret;
> +
> + if (pm_runtime_suspended(&tw9900->client->dev))
> + return 0;
> +
> + /* v4l2_ctrl_lock() locks tw9900->mutex. */
> + switch (ctrl->id) {
> + case V4L2_CID_BRIGHTNESS:
> + ret = tw9900_write_reg(tw9900->client, TW9900_REG_BRIGHT_CTL,
> + (u8)ctrl->val);
> + break;
> + case V4L2_CID_CONTRAST:
> + ret = tw9900_write_reg(tw9900->client, TW9900_REG_CONTRAST_CTL,
> + (u8)ctrl->val);
> + break;
> + default:
> + ret = -EINVAL;
> + break;
> + }
> +
> + return ret;
> +}
> +
> +static int tw9900_s_stream(struct v4l2_subdev *sd, int on)
> +{
> + struct tw9900 *tw9900 = to_tw9900(sd);
> + struct i2c_client *client = tw9900->client;
> + int ret;
> +
> + if (tw9900->streaming == on)
> + return 0;
You need this check to be mutex-protected.
> +
> + if (on) {
> + ret = pm_runtime_get_sync(&client->dev);
You should use pm_runtime_resume_and_get instead...
> + if (ret < 0) {
> + pm_runtime_put_noidle(&client->dev);
... which will gracefull handle this too.
> + return ret;
> + }
> +
> + mutex_lock(&tw9900->mutex);
> +
> + ret = __v4l2_ctrl_handler_setup(sd->ctrl_handler);
> + if (ret)
> + goto err_unlock;
> +
> + ret = tw9900_write_array(tw9900->client,
> + tw9900->cur_mode->reg_list,
> + tw9900->cur_mode->n_regs);
> + if (ret)
> + goto err_unlock;
> +
> + ret = tw9900_write_reg(client, TW9900_REG_OUT_FMT_CTL,
> + TW9900_REG_OUT_FMT_CTL_STREAMING);
> + if (ret)
> + goto err_unlock;
> +
> + } else {
> + mutex_lock(&tw9900->mutex);
> +
> + ret = tw9900_write_reg(client, TW9900_REG_OUT_FMT_CTL,
> + TW9900_REG_OUT_FMT_CTL_STANDBY);
> + if (ret)
> + goto err_unlock;
> +
> + pm_runtime_put(&client->dev);
You need to call this outside of the lock since it might call suspend (and
deadlock).
> + }
> +
> + tw9900->streaming = on;
> + mutex_unlock(&tw9900->mutex);
> +
> + return 0;
> +
> +err_unlock:
> + mutex_unlock(&tw9900->mutex);
> + pm_runtime_put(&client->dev);
> +
> + return ret;
> +}
> +
> +static int tw9900_runtime_resume(struct device *dev)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + struct v4l2_subdev *sd = i2c_get_clientdata(client);
> + struct tw9900 *tw9900 = to_tw9900(sd);
> +
> + return tw9900_power_on(tw9900);
> +}
> +
> +static int tw9900_runtime_suspend(struct device *dev)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + struct v4l2_subdev *sd = i2c_get_clientdata(client);
> + struct tw9900 *tw9900 = to_tw9900(sd);
> +
> + tw9900_power_off(tw9900);
> +
> + return 0;
> +}
> +
> +static int tw9900_subscribe_event(struct v4l2_subdev *sd,
> + struct v4l2_fh *fh,
> + struct v4l2_event_subscription *sub)
> +{
> + switch (sub->type) {
> + case V4L2_EVENT_SOURCE_CHANGE:
> + return v4l2_src_change_event_subdev_subscribe(sd, fh, sub);
> + case V4L2_EVENT_CTRL:
> + return v4l2_ctrl_subdev_subscribe_event(sd, fh, sub);
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static int tw9900_s_std(struct v4l2_subdev *sd, v4l2_std_id std)
> +{
> + struct tw9900 *tw9900 = to_tw9900(sd);
> + const struct tw9900_mode *mode;
> + int i, ret = 0;
> +
> + if (!(std & (V4L2_STD_NTSC | V4L2_STD_PAL)))
> + return -EINVAL;
> +
> + mutex_lock(&tw9900->mutex);
> +
> + for (i = 0; i < ARRAY_SIZE(supported_modes); i++)
> + if (supported_modes[i].std & std)
> + mode = &supported_modes[i];
> + if (!mode) {
> + ret = -EINVAL;
> + goto out_unlock;
> + }
You can lock here, the list of supported modes is not going to change.
> +
> + tw9900->cur_mode = mode;
> +
> +out_unlock:
> + mutex_unlock(&tw9900->mutex);
> +
> + return ret;
> +}
> +
> +static int tw9900_get_stream_std(struct tw9900 *tw9900,
> + v4l2_std_id *std)
> +{
> + int cur_std, ret;
> +
> + lockdep_assert_held(&tw9900->mutex);
> +
> + ret = tw9900_read_reg(tw9900->client, TW9900_REG_STD_SEL);
> + if (ret < 0) {
> + *std = V4L2_STD_UNKNOWN;
> + return ret;
> + }
> +
> + cur_std = FIELD_GET(TW9900_STDNOW_MASK, ret);
> + switch (cur_std) {
> + case TW9900_STD_NTSC_M:
> + *std = V4L2_STD_NTSC;
> + break;
> + case TW9900_STD_PAL_BDGHI:
> + *std = V4L2_STD_PAL;
> + break;
> + case TW9900_STD_AUTO:
> + *std = V4L2_STD_UNKNOWN;
> + break;
> + default:
> + *std = V4L2_STD_UNKNOWN;
> + break;
> + }
> +
> + return 0;
> +}
> +
> +static int tw9900_g_std(struct v4l2_subdev *sd, v4l2_std_id *std)
> +{
> + struct tw9900 *tw9900 = to_tw9900(sd);
> +
> + mutex_lock(&tw9900->mutex);
> + *std = tw9900->cur_mode->std;
> + mutex_unlock(&tw9900->mutex);
> +
> + return 0;
> +}
> +
> +static int tw9900_start_autodetect(struct tw9900 *tw9900)
> +{
> + int ret;
> +
> + lockdep_assert_held(&tw9900->mutex);
> +
> + ret = tw9900_write_reg(tw9900->client, TW9900_REG_STDR,
> + BIT(TW9900_STD_NTSC_M) |
> + BIT(TW9900_STD_PAL_BDGHI));
> + if (ret)
> + return ret;
> +
> + ret = tw9900_write_reg(tw9900->client, TW9900_REG_STD_SEL,
> + TW9900_STD_AUTO);
> + if (ret)
> + return ret;
> +
> + ret = tw9900_write_reg(tw9900->client, TW9900_REG_STDR,
> + BIT(TW9900_STD_NTSC_M) |
> + BIT(TW9900_STD_PAL_BDGHI) |
> + BIT(TW9900_STD_AUTO));
> + if (ret)
> + return ret;
> +
> + /*
> + * Autodetect takes a while to start, and during the starting sequence
> + * the autodetection status is reported as done.
> + */
> + msleep(30);
> +
> + return 0;
> +}
> +
> +static int tw9900_detect_done(struct tw9900 *tw9900, bool *done)
> +{
> + int ret;
> +
> + lockdep_assert_held(&tw9900->mutex);
> +
> + ret = tw9900_read_reg(tw9900->client, TW9900_REG_STD_SEL);
> + if (ret < 0)
> + return ret;
> +
> + *done = !(ret & TW9900_REG_STD_SEL_AUTODETECT_IN_PROGRESS);
> +
> + return 0;
> +}
> +
> +static int tw9900_querystd(struct v4l2_subdev *sd, v4l2_std_id *std)
> +{
> + struct tw9900 *tw9900 = to_tw9900(sd);
> + bool done = false;
> + int i, ret;
> +
> + if (tw9900->streaming)
> + return -EBUSY;
You need this to be locked.
> +
> + ret = pm_runtime_get_sync(&tw9900->client->dev);
pm_runtime_resume_and_get here too.
> + if (ret < 0) {
> + pm_runtime_put_noidle(&tw9900->client->dev);
> + return ret;
> + }
> +
> + mutex_lock(&tw9900->mutex);
> +
> + ret = tw9900_start_autodetect(tw9900);
> + if (ret)
> + goto out_unlock;
> +
> + for (i = 0; i < TW9900_VIDEO_POLL_TRIES; i++) {
> + ret = tw9900_detect_done(tw9900, &done);
> + if (ret)
> + goto out_unlock;
> +
> + if (done)
> + break;
> +
> + msleep(20);
> + }
> +
> + if (!done) {
> + ret = -ETIMEDOUT;
> + goto out_unlock;
> + }
> +
> + ret = tw9900_get_stream_std(tw9900, std);
> +
> +out_unlock:
> + mutex_unlock(&tw9900->mutex);
> + pm_runtime_put(&tw9900->client->dev);
> +
> + return ret;
> +}
> +
> +static int tw9900_g_tvnorms(struct v4l2_subdev *sd, v4l2_std_id *std)
> +{
> + *std = V4L2_STD_NTSC | V4L2_STD_PAL;
> +
> + return 0;
> +}
> +
> +static const struct dev_pm_ops tw9900_pm_ops = {
> + SET_RUNTIME_PM_OPS(tw9900_runtime_suspend,
> + tw9900_runtime_resume, NULL)
The macro is not useful as soon as you depend on PM, so you can just directly
register callbacks for runtime_suspend/runtime_resume here.
> +};
Also you should move the definition closer to the i2c_driver definition.
> +
> +static int tw9900_g_input_status(struct v4l2_subdev *sd, u32 *status)
> +{
> + struct tw9900 *tw9900 = to_tw9900(sd);
> + int ret;
> +
> + *status = V4L2_IN_ST_NO_SIGNAL;
> +
> + ret = pm_runtime_get_sync(&tw9900->client->dev);
pm_runtime_resume_and_get here too.
> + if (ret < 0) {
> + pm_runtime_put_noidle(&tw9900->client->dev);
> + return ret;
> + }
> +
> + mutex_lock(&tw9900->mutex);
> + ret = tw9900_read_reg(tw9900->client, TW9900_REG_CHIP_STATUS);
> + mutex_unlock(&tw9900->mutex);
> +
You can put the call to pm_runtime_put unconditionally here: the return code
value is not going to change because we cut power ;)
> + if (ret < 0) {
> + pm_runtime_put(&tw9900->client->dev);
> + return ret;
> + }
> +
> + *status = ret & TW9900_REG_CHIP_STATUS_HLOCK ? 0 : V4L2_IN_ST_NO_SIGNAL;
> +
> + pm_runtime_put(&tw9900->client->dev);
> +
> + return 0;
> +}
> +
> +static const struct v4l2_subdev_core_ops tw9900_core_ops = {
> + .subscribe_event = tw9900_subscribe_event,
> + .unsubscribe_event = v4l2_event_subdev_unsubscribe,
> +};
> +
> +static const struct v4l2_subdev_video_ops tw9900_video_ops = {
> + .s_std = tw9900_s_std,
> + .g_std = tw9900_g_std,
> + .querystd = tw9900_querystd,
> + .g_tvnorms = tw9900_g_tvnorms,
> + .g_input_status = tw9900_g_input_status,
> + .s_stream = tw9900_s_stream,
> +};
> +
> +static const struct v4l2_subdev_pad_ops tw9900_pad_ops = {
> + .enum_mbus_code = tw9900_enum_mbus_code,
Looks like there's one not-needed tab for alignment here.
> + .get_fmt = tw9900_get_fmt,
> + .set_fmt = tw9900_set_fmt,
> +};
> +
> +static const struct v4l2_subdev_ops tw9900_subdev_ops = {
> + .core = &tw9900_core_ops,
> + .video = &tw9900_video_ops,
> + .pad = &tw9900_pad_ops,
> +};
> +
> +static const struct v4l2_ctrl_ops tw9900_ctrl_ops = {
> + .s_ctrl = tw9900_s_ctrl,
> +};
> +
> +static int tw9900_check_id(struct tw9900 *tw9900,
> + struct i2c_client *client)
> +{
> + struct device *dev = &tw9900->client->dev;
> + int ret;
> +
> + mutex_lock(&tw9900->mutex);
> + ret = tw9900_read_reg(client, TW9900_CHIP_ID);
> + mutex_unlock(&tw9900->mutex);
> +
> + if (ret < 0)
> + return ret;
> +
> + if (ret != TW9900_CHIP_ID) {
> + dev_err(dev, "Unexpected decoder id %#x\n", ret);
> + return -ENODEV;
> + }
> +
> + return 0;
> +}
> +
> +static int tw9900_probe(struct i2c_client *client)
> +{
> + struct device *dev = &client->dev;
> + struct v4l2_ctrl_handler *hdl;
> + struct tw9900 *tw9900;
> + int ret = 0;
> +
> + tw9900 = devm_kzalloc(dev, sizeof(*tw9900), GFP_KERNEL);
> + if (!tw9900)
> + return -ENOMEM;
> +
> + tw9900->client = client;
> + tw9900->cur_mode = &supported_modes[0];
> +
> + tw9900->reset_gpio = devm_gpiod_get_optional(dev, "reset",
> + GPIOD_OUT_LOW);
> + if (IS_ERR(tw9900->reset_gpio))
> + return dev_err_probe(dev, PTR_ERR(tw9900->reset_gpio),
> + "Failed to get reset gpio\n");
> +
> + tw9900->regulator = devm_regulator_get(&tw9900->client->dev, "vdd");
> + if (IS_ERR(tw9900->regulator))
> + return dev_err_probe(dev, PTR_ERR(tw9900->regulator),
> + "Failed to get power regulator\n");
> +
> + v4l2_i2c_subdev_init(&tw9900->subdev, client, &tw9900_subdev_ops);
> + tw9900->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
> + V4L2_SUBDEV_FL_HAS_EVENTS;
> +
> + mutex_init(&tw9900->mutex);
> +
> + hdl = &tw9900->hdl;
> +
> + ret = v4l2_ctrl_handler_init(hdl, 2);
> + if (ret)
> + return ret;
> +
> + hdl->lock = &tw9900->mutex;
> +
> + v4l2_ctrl_new_std(hdl, &tw9900_ctrl_ops, V4L2_CID_BRIGHTNESS,
> + -128, 127, 1, 0);
> + v4l2_ctrl_new_std(hdl, &tw9900_ctrl_ops, V4L2_CID_CONTRAST,
> + 0, 255, 1, 0x60);
> +
> + tw9900->subdev.ctrl_handler = hdl;
> + if (hdl->error) {
> + ret = hdl->error;
> + goto err_free_handler;
> + }
> +
> + ret = tw9900_power_on(tw9900);
> + if (ret)
> + goto err_free_handler;
> +
> + ret = tw9900_check_id(tw9900, client);
> + if (ret)
> + goto err_power_off;
I would move this check after the rpm init so you can use the regular
pm_runtime_resume_and_get. Also don't forget to put because we still don't
want to keep the device powered at all times!
> +
> + tw9900->pad.flags = MEDIA_PAD_FL_SOURCE;
> + tw9900->subdev.entity.function = MEDIA_ENT_F_DV_DECODER;
> +
> + ret = media_entity_pads_init(&tw9900->subdev.entity, 1, &tw9900->pad);
> + if (ret < 0)
> + goto err_power_off;
> +
> + ret = v4l2_async_register_subdev(&tw9900->subdev);
> + if (ret) {
> + dev_err(dev, "v4l2 async register subdev failed\n");
> + goto err_clean_entity;
> + }
But we still want to keep this at the end (after checking the chip id).
> +
> + pm_runtime_set_active(dev);
Don't set it active, set it to suspended instead with pm_runtime_set_suspended.
> + pm_runtime_enable(dev);
> + pm_runtime_idle(dev);
No need for this.
> +
> + return 0;
> +
> +err_clean_entity:
> + media_entity_cleanup(&tw9900->subdev.entity);
> +err_power_off:
> + tw9900_power_off(tw9900);
> +err_free_handler:
> + v4l2_ctrl_handler_free(hdl);
> + mutex_destroy(&tw9900->mutex);
> +
> + return ret;
> +}
> +
> +static void tw9900_remove(struct i2c_client *client)
> +{
> + struct v4l2_subdev *sd = i2c_get_clientdata(client);
> + struct tw9900 *tw9900 = to_tw9900(sd);
> +
> + v4l2_async_unregister_subdev(sd);
> + media_entity_cleanup(&sd->entity);
> + v4l2_ctrl_handler_free(sd->ctrl_handler);
> +
> + pm_runtime_disable(&client->dev);
> + if (!pm_runtime_status_suspended(&client->dev))
> + tw9900_power_off(tw9900);
If all calls are balanced you should not need this. You might still want to
call pm_runtime_suspend under this condition, but you need to do it before you
call pm_runtime_disable.
> +
> + pm_runtime_set_suspended(&client->dev);
This is not useful, you can remove it.
> + mutex_destroy(&tw9900->mutex);
> +}
> +
> +static const struct i2c_device_id tw9900_id[] = {
> + { "tw9900", 0 },
> + { }
> +};
> +MODULE_DEVICE_TABLE(i2c, tw9900_id);
> +
> +static const struct of_device_id tw9900_of_match[] = {
> + { .compatible = "techwell,tw9900" },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, tw9900_of_match);
> +
> +static struct i2c_driver tw9900_i2c_driver = {
> + .driver = {
> + .name = "tw9900",
> + .pm = &tw9900_pm_ops,
> + .of_match_table = tw9900_of_match,
> + },
> + .probe = tw9900_probe,
> + .remove = tw9900_remove,
> + .id_table = tw9900_id,
> +};
> +
> +module_i2c_driver(tw9900_i2c_driver);
> +
> +MODULE_DESCRIPTION("tw9900 decoder driver");
> +MODULE_LICENSE("GPL");
> --
> 2.41.0
>
--
Paul Kocialkowski, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com