Re: [V1, 2/2] media: i2c: Add more sensor mode for ov8856 camera sensor
From: Tomasz Figa <tfiga@chromium.org>
Date: 2019-08-23 10:01:26
Also in:
linux-arm-kernel, linux-media, linux-mediatek
Hi Dongchun, On Thu, Aug 08, 2019 at 05:22:15PM +0800, dongchun.zhu@mediatek.com wrote:
From: Dongchun Zhu <redacted> This patch mainly adds two more sensor modes for OV8856 image sensor. The OV8856 driver currently supports output format: 10-bit Raw, the resolution of 1632*1224 and 3264*2448, and the bayer order of BGGR. The hardware version also differs in some OTP regiser, as well as PLL register setting. Signed-off-by: Dongchun Zhu <redacted> --- drivers/media/i2c/ov8856.c | 624 ++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 621 insertions(+), 3 deletions(-)
Thanks for the patch! Please see my comments inline.
quoted hunk ↗ jump to hunk
diff --git a/drivers/media/i2c/ov8856.c b/drivers/media/i2c/ov8856.c index cd347d6..e0610b6 100644 --- a/drivers/media/i2c/ov8856.c +++ b/drivers/media/i2c/ov8856.c@@ -1,12 +1,15 @@ // SPDX-License-Identifier: GPL-2.0 // Copyright (c) 2019 Intel Corporation. +#include <linux/clk.h> #include <asm/unaligned.h> #include <linux/acpi.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 +22,7 @@ #define OV8856_LINK_FREQ_180MHZ 180000000ULL #define OV8856_SCLK 144000000ULL #define OV8856_MCLK 19200000 +#define OV8856_XVCLK_FREQ 24000000 #define OV8856_DATA_LANES 4 #define OV8856_RGB_DEPTH 10@@ -29,6 +33,18 @@ #define OV8856_MODE_STANDBY 0x00 #define OV8856_MODE_STREAMING 0x01 +/* define 1B module */ +#define OV8856_1B_MODULE 0x02 + +/* otp sram register */ +#define OV8856_OTP_REG 0x700f
This isn't a register. I believe the OTP read-out buffer is at 0x7000 and 0xf is the offset of the byte in the OTP that means the module revision.
+#define OV8856_OTP_REG_ONE 0x3d84 +#define OV8856_OTP_REG_TWO 0x3d81
These registers are definitely not "ONE" and "TWO". Please use proper names as per the datasheet.
+ +/* clock register */ +#define OV8856_CLK_REG 0x3614 +#define OV8856_CLK_REG_1B_VAL 0x20
Same here. These don't look like the real names of the register and bit field.
quoted hunk ↗ jump to hunk
+ /* vertical-timings from sensor */ #define OV8856_REG_VTS 0x380e #define OV8856_VTS_MAX 0x7fff@@ -64,6 +80,14 @@ #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 */ +}; + +#define OV8856_NUM_SUPPLIES ARRAY_SIZE(ov8856_supply_names) + enum { OV8856_LINK_FREQ_720MBPS, OV8856_LINK_FREQ_360MBPS,@@ -316,6 +340,208 @@ static const struct ov8856_reg mode_3280x2464_regs[] = { {0x5e00, 0x00} }; +static const struct ov8856_reg mode_3264x2448_regs[] = { + {0x0103, 0x01}, + {0x0302, 0x3c}, + {0x0303, 0x01}, + {0x031e, 0x0c}, + {0x3000, 0x00}, + {0x300e, 0x00}, + {0x3010, 0x00}, + {0x3015, 0x84}, + {0x3018, 0x72}, + {0x3021, 0x23}, + {0x3033, 0x24}, + {0x3500, 0x00}, + {0x3501, 0x9a}, + {0x3502, 0x20}, + {0x3503, 0x08}, + {0x3505, 0x83}, + {0x3508, 0x01}, + {0x3509, 0x80}, + {0x350c, 0x00}, + {0x350d, 0x80}, + {0x350e, 0x04}, + {0x350f, 0x00}, + {0x3510, 0x00}, + {0x3511, 0x02}, + {0x3512, 0x00}, + {0x3600, 0x72}, + {0x3601, 0x40}, + {0x3602, 0x30}, + {0x3610, 0xc5}, + {0x3611, 0x58}, + {0x3612, 0x5c}, + {0x3613, 0xca}, + {0x3614, 0x60}, + {0x3628, 0xff}, + {0x3629, 0xff}, + {0x362a, 0xff}, + {0x3633, 0x10}, + {0x3634, 0x10}, + {0x3635, 0x10}, + {0x3636, 0x10}, + {0x3663, 0x08}, + {0x3669, 0x34}, + {0x366d, 0x00}, + {0x366e, 0x10}, + {0x3706, 0x86}, + {0x370b, 0x7e}, + {0x3714, 0x23}, + {0x3730, 0x12}, + {0x3733, 0x10}, + {0x3764, 0x00}, + {0x3765, 0x00}, + {0x3769, 0x62}, + {0x376a, 0x2a}, + {0x376b, 0x30}, + {0x3780, 0x00}, + {0x3781, 0x24}, + {0x3782, 0x00}, + {0x3783, 0x23}, + {0x3798, 0x2f}, + {0x37a1, 0x60}, + {0x37a8, 0x6a}, + {0x37ab, 0x3f}, + {0x37c2, 0x04}, + {0x37c3, 0xf1}, + {0x37c9, 0x80}, + {0x37cb, 0x16}, + {0x37cc, 0x16}, + {0x37cd, 0x16}, + {0x37ce, 0x16}, + {0x3800, 0x00}, + {0x3801, 0x00}, + {0x3802, 0x00}, + {0x3803, 0x0c}, + {0x3804, 0x0c}, + {0x3805, 0xdf}, + {0x3806, 0x09}, + {0x3807, 0xa3}, + {0x3808, 0x0c}, + {0x3809, 0xc0}, + {0x380a, 0x09}, + {0x380b, 0x90}, + {0x380c, 0x07}, + {0x380d, 0x8c}, + {0x380e, 0x09}, + {0x380f, 0xb2}, + {0x3810, 0x00}, + {0x3811, 0x04}, + {0x3812, 0x00}, + {0x3813, 0x02}, + {0x3814, 0x01}, + {0x3815, 0x01}, + {0x3816, 0x00}, + {0x3817, 0x00}, + {0x3818, 0x00}, + {0x3819, 0x00}, + {0x3820, 0x80}, + {0x3821, 0x46}, + {0x382a, 0x01}, + {0x382b, 0x01}, + {0x3830, 0x06}, + {0x3836, 0x02}, + {0x3862, 0x04}, + {0x3863, 0x08}, + {0x3cc0, 0x33}, + {0x3d85, 0x17}, + {0x3d8c, 0x73}, + {0x3d8d, 0xde}, + {0x4001, 0xe0}, + {0x4003, 0x40}, + {0x4008, 0x00}, + {0x4009, 0x0b}, + {0x400a, 0x00}, + {0x400b, 0x84}, + {0x400f, 0x80}, + {0x4010, 0xf0}, + {0x4011, 0xff}, + {0x4012, 0x02}, + {0x4013, 0x01}, + {0x4014, 0x01}, + {0x4015, 0x01}, + {0x4042, 0x00}, + {0x4043, 0x80}, + {0x4044, 0x00}, + {0x4045, 0x80}, + {0x4046, 0x00}, + {0x4047, 0x80}, + {0x4048, 0x00}, + {0x4049, 0x80}, + {0x4041, 0x03}, + {0x404c, 0x20}, + {0x404d, 0x00}, + {0x404e, 0x20}, + {0x4203, 0x80}, + {0x4307, 0x30}, + {0x4317, 0x00}, + {0x4502, 0x50}, + {0x4503, 0x08}, + {0x4601, 0x80}, + {0x4800, 0x44}, + {0x4816, 0x53}, + {0x481b, 0x50}, + {0x481f, 0x27}, + {0x4823, 0x3c}, + {0x482b, 0x00}, + {0x4831, 0x66}, + {0x4837, 0x16}, + {0x483c, 0x0f}, + {0x484b, 0x05}, + {0x5000, 0x77}, + {0x5001, 0x0a}, + {0x5003, 0xc8}, + {0x5004, 0x04}, + {0x5006, 0x00}, + {0x5007, 0x00}, + {0x502e, 0x03}, + {0x5030, 0x41}, + {0x5780, 0x14}, + {0x5781, 0x0f}, + {0x5782, 0x44}, + {0x5783, 0x02}, + {0x5784, 0x01}, + {0x5785, 0x01}, + {0x5786, 0x00}, + {0x5787, 0x04}, + {0x5788, 0x02}, + {0x5789, 0x0f}, + {0x578a, 0xfd}, + {0x578b, 0xf5}, + {0x578c, 0xf5}, + {0x578d, 0x03}, + {0x578e, 0x08}, + {0x578f, 0x0c}, + {0x5790, 0x08}, + {0x5791, 0x04}, + {0x5792, 0x00}, + {0x5793, 0x52}, + {0x5794, 0xa3}, + {0x5795, 0x02}, + {0x5796, 0x20}, + {0x5797, 0x20}, + {0x5798, 0xd5}, + {0x5799, 0xd5}, + {0x579a, 0x00}, + {0x579b, 0x50}, + {0x579c, 0x00}, + {0x579d, 0x2c}, + {0x579e, 0x0c}, + {0x579f, 0x40}, + {0x57a0, 0x09}, + {0x57a1, 0x40}, + {0x59f8, 0x3d}, + {0x5a08, 0x02}, + {0x5b00, 0x02}, + {0x5b01, 0x10}, + {0x5b02, 0x03}, + {0x5b03, 0xcf}, + {0x5b05, 0x6c}, + {0x5e00, 0x00}, + {0x5e10, 0xfc} +}; +
It would be better if we could find the differences between the two arrays and handle them incrementally. [snip]
+static int ov8856_update_otp_reg(struct ov8856 *ov8856)
+{
+ int ret;
+
+ ret = ov8856_write_reg(ov8856, OV8856_REG_MODE_SELECT,
+ OV8856_REG_VALUE_08BIT, OV8856_MODE_STREAMING);
+ if (ret)
+ return ret;
+
+ ret = ov8856_write_reg(ov8856, OV8856_OTP_REG_ONE,
+ OV8856_REG_VALUE_08BIT, OV8856_MODE_STANDBY);
+ if (ret)
+ return ret;
+
+ return ov8856_write_reg(ov8856, OV8856_OTP_REG_TWO,
+ OV8856_REG_VALUE_08BIT, OV8856_MODE_STREAMING);Hmm, this doesn't sound right. The OTP register doesn't have anything to do with streaming. Also we should stop streaming at the end.
quoted hunk ↗ jump to hunk
+} + static int ov8856_set_ctrl(struct v4l2_ctrl *ctrl) { struct ov8856 *ov8856 = container_of(ctrl->handler,@@ -825,7 +1302,13 @@ static void ov8856_update_pad_format(const struct ov8856_mode *mode, { fmt->width = mode->width; fmt->height = mode->height; - fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10; + + /* Bayer Order is determined by image resolution */ + if (fmt->width == 3264 || fmt->width == 1632)
Could we instead set the bayer order in the mode struct?
quoted hunk ↗ jump to hunk
+ fmt->code = MEDIA_BUS_FMT_SBGGR10_1X10; + else + fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10; + fmt->field = V4L2_FIELD_NONE; }@@ -850,6 +1333,17 @@ static int ov8856_start_streaming(struct ov8856 *ov8856) return ret; } + /* update R3614 for 1B module */
What's R3614?
quoted hunk ↗ jump to hunk
+ if (ov8856->is_1B_module) { + ret = ov8856_write_reg(ov8856, OV8856_CLK_REG, + OV8856_REG_VALUE_08BIT, + OV8856_CLK_REG_1B_VAL); + if (ret) { + dev_err(&client->dev, "failed to set R3614"); + return ret; + } + } + ret = __v4l2_ctrl_handler_setup(ov8856->sd.ctrl_handler); if (ret) return ret;@@ -882,6 +1376,8 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable) if (ov8856->streaming == enable) return 0; + dev_dbg(&client->dev, "hardware version: (%d)\n", ov8856->is_1B_module); + mutex_lock(&ov8856->mutex); if (enable) { ret = pm_runtime_get_sync(&client->dev);@@ -908,6 +1404,54 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable) return ret; } +/* Calculate the delay in us by clock rate and clock cycles */ +static inline u32 ov8856_cal_delay(u32 cycles) +{ + return DIV_ROUND_UP(cycles, OV8856_XVCLK_FREQ / 1000 / 1000); +} + +static int __ov8856_power_on(struct ov8856 *ov8856) +{ + int ret; + u32 delay_us; + struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd); + + 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, 1);
According to my datasheet, this sensor doesn't have a reset pin. The one I can see there is XSHUTDN, which I would call "n_shutdn" here.
+
+ ret = regulator_bulk_enable(OV8856_NUM_SUPPLIES, ov8856->supplies);
+ if (ret < 0) {
+ dev_err(&client->dev, "Failed to enable regulators\n");
+ goto disable_clk;
+ }
+
+ gpiod_set_value_cansleep(ov8856->reset_gpio, 0);According to the datasheet, XSHUTDN should be 0 for shutdown and 1 for running. Why is it the other way around here?
+ + /* 8192 cycles prior to first SCCB transaction */ + delay_us = ov8856_cal_delay(8192);
If we pass a constant to the function and the function itself only uses constants inside, could we just define a constant delay instead?
+ usleep_range(delay_us * 2, delay_us * 4);
Normally one one just give some small delta here, like +/- 100 us.
quoted hunk ↗ jump to hunk
+ + return 0; + +disable_clk: + clk_disable_unprepare(ov8856->xvclk); + + return ret; +} + +static void __ov8856_power_off(struct ov8856 *ov8856) +{ + clk_disable_unprepare(ov8856->xvclk); + gpiod_set_value_cansleep(ov8856->reset_gpio, 1); + + regulator_bulk_disable(OV8856_NUM_SUPPLIES, ov8856->supplies); +} + static int __maybe_unused ov8856_suspend(struct device *dev) { struct i2c_client *client = to_i2c_client(dev);@@ -915,8 +1459,8 @@ static int __maybe_unused ov8856_suspend(struct device *dev) struct ov8856 *ov8856 = to_ov8856(sd); mutex_lock(&ov8856->mutex); - if (ov8856->streaming) - ov8856_stop_streaming(ov8856); + + __ov8856_power_off(ov8856);
This change is incorrect because it will power off even if the device was already powered off, causing reference count mismatch. The original code was okay.
quoted hunk ↗ jump to hunk
mutex_unlock(&ov8856->mutex);@@ -1089,6 +1633,20 @@ static int ov8856_identify_module(struct ov8856 *ov8856) return -ENXIO; } + /* set R3614 to distinguish harward versions */
hardware
+ ret = ov8856_update_otp_reg(ov8856);
+ if (ret) {
+ dev_err(&client->dev, "failed to set otp register");
+ return ret;
+ }
+
+ ret = ov8856_read_reg(ov8856, OV8856_OTP_REG,
+ OV8856_REG_VALUE_08BIT, &val);
+ if (ret)
+ return ret;
+
+ ov8856->is_1B_module = (val == OV8856_1B_MODULE) ? 1 : 0;I'd rename ov8856_update_otp_reg() to ov8856_check_revision() and move the few lines above to that function too.
quoted hunk ↗ jump to hunk
+ return 0; }@@ -1164,11 +1722,27 @@ static int ov8856_remove(struct i2c_client *client) media_entity_cleanup(&sd->entity); v4l2_ctrl_handler_free(sd->ctrl_handler); pm_runtime_disable(&client->dev); + if (!pm_runtime_status_suspended(&client->dev)) + __ov8856_power_off(ov8856); + pm_runtime_set_suspended(&client->dev); mutex_destroy(&ov8856->mutex); return 0; } +static int ov8856_configure_regulators(struct ov8856 *ov8856) +{ + struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd); + int i; + + for (i = 0; i < OV8856_NUM_SUPPLIES; i++) + ov8856->supplies[i].supply = ov8856_supply_names[i]; + + return devm_regulator_bulk_get(&client->dev, + OV8856_NUM_SUPPLIES, + ov8856->supplies); +}
There is not much value in having a dedicated function just to call one more function. Could you move back to the caller?
quoted hunk ↗ jump to hunk
+ static int ov8856_probe(struct i2c_client *client) { struct ov8856 *ov8856;@@ -1186,6 +1760,40 @@ 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 (IS_ERR(ov8856->xvclk)) { + dev_err(&client->dev, "Failed to get xvclk\n"); + return -EINVAL; + } + + ret = clk_set_rate(ov8856->xvclk, OV8856_XVCLK_FREQ);
We should get the frequency from the DT bindings.
quoted hunk ↗ jump to hunk
+ if (ret < 0) { + dev_err(&client->dev, "Failed to set xvclk rate (24MHz)\n"); + return ret; + } + if (clk_get_rate(ov8856->xvclk) != OV8856_XVCLK_FREQ) + dev_warn(&client->dev, + "xvclk mismatched, modes are based on 24MHz\n"); + + ov8856->reset_gpio = devm_gpiod_get(&client->dev, + "reset", + GPIOD_OUT_LOW); + if (IS_ERR(ov8856->reset_gpio)) { + dev_err(&client->dev, "Failed to get reset-gpios\n"); + return -EINVAL; + } + + ret = ov8856_configure_regulators(ov8856); + if (ret) { + dev_err(&client->dev, "Failed to get power regulators\n"); + return ret; + } + + ret = __ov8856_power_on(ov8856); + if (ret) + goto probe_error_v4l2_ctrl_handler_free; + ret = ov8856_identify_module(ov8856); if (ret) { dev_err(&client->dev, "failed to find sensor: %d", ret);@@ -1251,11 +1859,21 @@ static const struct acpi_device_id ov8856_acpi_ids[] = { MODULE_DEVICE_TABLE(acpi, ov8856_acpi_ids); #endif +#if IS_ENABLED(CONFIG_OF) +static const struct of_device_id ov8856_of_match[] = { + { .compatible = "ovti,ov8856" }, + {}, +}; +
nit: Unnecessary blank line. Best regards, Tomasz