Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1283 insertions, 0 deletions

diff --git a/drivers/media/i2c/mt9v111.c b/drivers/media/i2c/mt9v111.c
new file mode 100644
index 000000000..bb41bea95
--- /dev/null
+++ b/drivers/media/i2c/mt9v111.c
@@ -0,0 +1,1283 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * V4L2 sensor driver for Aptina MT9V111 image sensor
+ * Copyright (C) 2018 Jacopo Mondi <jacopo@jmondi.org>
+ *
+ * Based on mt9v032 driver
+ * Copyright (C) 2010, Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ * Copyright (C) 2008, Guennadi Liakhovetski <kernel@pengutronix.de>
+ *
+ * Based on mt9v011 driver
+ * Copyright (c) 2009 Mauro Carvalho Chehab <mchehab@kernel.org>
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/videodev2.h>
+#include <linux/v4l2-mediabus.h>
+#include <linux/module.h>
+
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-fwnode.h>
+#include <media/v4l2-image-sizes.h>
+#include <media/v4l2-subdev.h>
+
+/*
+ * MT9V111 is a 1/4-Inch CMOS digital image sensor with an integrated
+ * Image Flow Processing (IFP) engine and a sensor core loosely based on
+ * MT9V011.
+ *
+ * The IFP can produce several output image formats from the sensor core
+ * output. This driver currently supports only YUYV format permutations.
+ *
+ * The driver allows manual frame rate control through s_frame_interval subdev
+ * operation or V4L2_CID_V/HBLANK controls, but it is known that the
+ * auto-exposure algorithm might modify the programmed frame rate. While the
+ * driver initially programs the sensor with auto-exposure and
+ * auto-white-balancing enabled, it is possible to disable them and more
+ * precisely control the frame rate.
+ *
+ * While it seems possible to instruct the auto-exposure control algorithm to
+ * respect a programmed frame rate when adjusting the pixel integration time,
+ * registers controlling this feature are not documented in the public
+ * available sensor manual used to develop this driver (09005aef80e90084,
+ * MT9V111_1.fm - Rev. G 1/05 EN).
+ */
+
+#define MT9V111_CHIP_ID_HIGH				0x82
+#define MT9V111_CHIP_ID_LOW				0x3a
+
+#define MT9V111_R01_ADDR_SPACE				0x01
+#define MT9V111_R01_IFP					0x01
+#define MT9V111_R01_CORE				0x04
+
+#define MT9V111_IFP_R06_OPMODE_CTRL			0x06
+#define		MT9V111_IFP_R06_OPMODE_CTRL_AWB_EN	BIT(1)
+#define		MT9V111_IFP_R06_OPMODE_CTRL_AE_EN	BIT(14)
+#define MT9V111_IFP_R07_IFP_RESET			0x07
+#define		MT9V111_IFP_R07_IFP_RESET_MASK		BIT(0)
+#define MT9V111_IFP_R08_OUTFMT_CTRL			0x08
+#define		MT9V111_IFP_R08_OUTFMT_CTRL_FLICKER	BIT(11)
+#define		MT9V111_IFP_R08_OUTFMT_CTRL_PCLK	BIT(5)
+#define MT9V111_IFP_R3A_OUTFMT_CTRL2			0x3a
+#define		MT9V111_IFP_R3A_OUTFMT_CTRL2_SWAP_CBCR	BIT(0)
+#define		MT9V111_IFP_R3A_OUTFMT_CTRL2_SWAP_YC	BIT(1)
+#define		MT9V111_IFP_R3A_OUTFMT_CTRL2_SWAP_MASK	GENMASK(2, 0)
+#define MT9V111_IFP_RA5_HPAN				0xa5
+#define MT9V111_IFP_RA6_HZOOM				0xa6
+#define MT9V111_IFP_RA7_HOUT				0xa7
+#define MT9V111_IFP_RA8_VPAN				0xa8
+#define MT9V111_IFP_RA9_VZOOM				0xa9
+#define MT9V111_IFP_RAA_VOUT				0xaa
+#define MT9V111_IFP_DECIMATION_MASK			GENMASK(9, 0)
+#define MT9V111_IFP_DECIMATION_FREEZE			BIT(15)
+
+#define MT9V111_CORE_R03_WIN_HEIGHT			0x03
+#define		MT9V111_CORE_R03_WIN_V_OFFS		2
+#define MT9V111_CORE_R04_WIN_WIDTH			0x04
+#define		MT9V111_CORE_R04_WIN_H_OFFS		114
+#define MT9V111_CORE_R05_HBLANK				0x05
+#define		MT9V111_CORE_R05_MIN_HBLANK		0x09
+#define		MT9V111_CORE_R05_MAX_HBLANK		GENMASK(9, 0)
+#define		MT9V111_CORE_R05_DEF_HBLANK		0x26
+#define MT9V111_CORE_R06_VBLANK				0x06
+#define		MT9V111_CORE_R06_MIN_VBLANK		0x03
+#define		MT9V111_CORE_R06_MAX_VBLANK		GENMASK(11, 0)
+#define		MT9V111_CORE_R06_DEF_VBLANK		0x04
+#define MT9V111_CORE_R07_OUT_CTRL			0x07
+#define		MT9V111_CORE_R07_OUT_CTRL_SAMPLE	BIT(4)
+#define MT9V111_CORE_R09_PIXEL_INT			0x09
+#define		MT9V111_CORE_R09_PIXEL_INT_MASK		GENMASK(11, 0)
+#define MT9V111_CORE_R0D_CORE_RESET			0x0d
+#define		MT9V111_CORE_R0D_CORE_RESET_MASK	BIT(0)
+#define MT9V111_CORE_RFF_CHIP_VER			0xff
+
+#define MT9V111_PIXEL_ARRAY_WIDTH			640
+#define MT9V111_PIXEL_ARRAY_HEIGHT			480
+
+#define MT9V111_MAX_CLKIN				27000000
+
+/* The default sensor configuration at startup time. */
+static struct v4l2_mbus_framefmt mt9v111_def_fmt = {
+	.width		= 640,
+	.height		= 480,
+	.code		= MEDIA_BUS_FMT_UYVY8_2X8,
+	.field		= V4L2_FIELD_NONE,
+	.colorspace	= V4L2_COLORSPACE_SRGB,
+	.ycbcr_enc	= V4L2_YCBCR_ENC_601,
+	.quantization	= V4L2_QUANTIZATION_LIM_RANGE,
+	.xfer_func	= V4L2_XFER_FUNC_SRGB,
+};
+
+struct mt9v111_dev {
+	struct device *dev;
+	struct i2c_client *client;
+
+	u8 addr_space;
+
+	struct v4l2_subdev sd;
+#if IS_ENABLED(CONFIG_MEDIA_CONTROLLER)
+	struct media_pad pad;
+#endif
+
+	struct v4l2_ctrl *auto_awb;
+	struct v4l2_ctrl *auto_exp;
+	struct v4l2_ctrl *hblank;
+	struct v4l2_ctrl *vblank;
+	struct v4l2_ctrl_handler ctrls;
+
+	/* Output image format and sizes. */
+	struct v4l2_mbus_framefmt fmt;
+	unsigned int fps;
+
+	/* Protects power up/down sequences. */
+	struct mutex pwr_mutex;
+	int pwr_count;
+
+	/* Protects stream on/off sequences. */
+	struct mutex stream_mutex;
+	bool streaming;
+
+	/* Flags to mark HW settings as not yet applied. */
+	bool pending;
+
+	/* Clock provider and system clock frequency. */
+	struct clk *clk;
+	u32 sysclk;
+
+	struct gpio_desc *oe;
+	struct gpio_desc *standby;
+	struct gpio_desc *reset;
+};
+
+#define sd_to_mt9v111(__sd) container_of((__sd), struct mt9v111_dev, sd)
+
+/*
+ * mt9v111_mbus_fmt - List all media bus formats supported by the driver.
+ *
+ * Only list the media bus code here. The image sizes are freely configurable
+ * in the pixel array sizes range.
+ *
+ * The desired frame interval, in the supported frame interval range, is
+ * obtained by configuring blanking as the sensor does not have a PLL but
+ * only a fixed clock divider that generates the output pixel clock.
+ */
+static struct mt9v111_mbus_fmt {
+	u32	code;
+} mt9v111_formats[] = {
+	{
+		.code	= MEDIA_BUS_FMT_UYVY8_2X8,
+	},
+	{
+		.code	= MEDIA_BUS_FMT_YUYV8_2X8,
+	},
+	{
+		.code	= MEDIA_BUS_FMT_VYUY8_2X8,
+	},
+	{
+		.code	= MEDIA_BUS_FMT_YVYU8_2X8,
+	},
+};
+
+static u32 mt9v111_frame_intervals[] = {5, 10, 15, 20, 30};
+
+/*
+ * mt9v111_frame_sizes - List sensor's supported resolutions.
+ *
+ * Resolution generated through decimation in the IFP block from the
+ * full VGA pixel array.
+ */
+static struct v4l2_rect mt9v111_frame_sizes[] = {
+	{
+		.width	= 640,
+		.height	= 480,
+	},
+	{
+		.width	= 352,
+		.height	= 288
+	},
+	{
+		.width	= 320,
+		.height	= 240,
+	},
+	{
+		.width	= 176,
+		.height	= 144,
+	},
+	{
+		.width	= 160,
+		.height	= 120,
+	},
+};
+
+/* --- Device I/O access --- */
+
+static int __mt9v111_read(struct i2c_client *c, u8 reg, u16 *val)
+{
+	struct i2c_msg msg[2];
+	__be16 buf;
+	int ret;
+
+	msg[0].addr = c->addr;
+	msg[0].flags = 0;
+	msg[0].len = 1;
+	msg[0].buf = &reg;
+
+	msg[1].addr = c->addr;
+	msg[1].flags = I2C_M_RD;
+	msg[1].len = 2;
+	msg[1].buf = (char *)&buf;
+
+	ret = i2c_transfer(c->adapter, msg, 2);
+	if (ret < 0) {
+		dev_err(&c->dev, "i2c read transfer error: %d\n", ret);
+		return ret;
+	}
+
+	*val = be16_to_cpu(buf);
+
+	dev_dbg(&c->dev, "%s: %x=%x\n", __func__, reg, *val);
+
+	return 0;
+}
+
+static int __mt9v111_write(struct i2c_client *c, u8 reg, u16 val)
+{
+	struct i2c_msg msg;
+	u8 buf[3] = { 0 };
+	int ret;
+
+	buf[0] = reg;
+	buf[1] = val >> 8;
+	buf[2] = val & 0xff;
+
+	msg.addr = c->addr;
+	msg.flags = 0;
+	msg.len = 3;
+	msg.buf = (char *)buf;
+
+	dev_dbg(&c->dev, "%s: %x = %x%x\n", __func__, reg, buf[1], buf[2]);
+
+	ret = i2c_transfer(c->adapter, &msg, 1);
+	if (ret < 0) {
+		dev_err(&c->dev, "i2c write transfer error: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int __mt9v111_addr_space_select(struct i2c_client *c, u16 addr_space)
+{
+	struct v4l2_subdev *sd = i2c_get_clientdata(c);
+	struct mt9v111_dev *mt9v111 = sd_to_mt9v111(sd);
+	u16 val;
+	int ret;
+
+	if (mt9v111->addr_space == addr_space)
+		return 0;
+
+	ret = __mt9v111_write(c, MT9V111_R01_ADDR_SPACE, addr_space);
+	if (ret)
+		return ret;
+
+	/* Verify address space has been updated */
+	ret = __mt9v111_read(c, MT9V111_R01_ADDR_SPACE, &val);
+	if (ret)
+		return ret;
+
+	if (val != addr_space)
+		return -EINVAL;
+
+	mt9v111->addr_space = addr_space;
+
+	return 0;
+}
+
+static int mt9v111_read(struct i2c_client *c, u8 addr_space, u8 reg, u16 *val)
+{
+	int ret;
+
+	/* Select register address space first. */
+	ret = __mt9v111_addr_space_select(c, addr_space);
+	if (ret)
+		return ret;
+
+	ret = __mt9v111_read(c, reg, val);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int mt9v111_write(struct i2c_client *c, u8 addr_space, u8 reg, u16 val)
+{
+	int ret;
+
+	/* Select register address space first. */
+	ret = __mt9v111_addr_space_select(c, addr_space);
+	if (ret)
+		return ret;
+
+	ret = __mt9v111_write(c, reg, val);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int mt9v111_update(struct i2c_client *c, u8 addr_space, u8 reg,
+			  u16 mask, u16 val)
+{
+	u16 current_val;
+	int ret;
+
+	/* Select register address space first. */
+	ret = __mt9v111_addr_space_select(c, addr_space);
+	if (ret)
+		return ret;
+
+	/* Read the current register value, then update it. */
+	ret = __mt9v111_read(c, reg, &current_val);
+	if (ret)
+		return ret;
+
+	current_val &= ~mask;
+	current_val |= (val & mask);
+	ret = __mt9v111_write(c, reg, current_val);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+/* --- Sensor HW operations --- */
+
+static int __mt9v111_power_on(struct v4l2_subdev *sd)
+{
+	struct mt9v111_dev *mt9v111 = sd_to_mt9v111(sd);
+	int ret;
+
+	ret = clk_prepare_enable(mt9v111->clk);
+	if (ret)
+		return ret;
+
+	clk_set_rate(mt9v111->clk, mt9v111->sysclk);
+
+	gpiod_set_value(mt9v111->standby, 0);
+	usleep_range(500, 1000);
+
+	gpiod_set_value(mt9v111->oe, 1);
+	usleep_range(500, 1000);
+
+	return 0;
+}
+
+static int __mt9v111_power_off(struct v4l2_subdev *sd)
+{
+	struct mt9v111_dev *mt9v111 = sd_to_mt9v111(sd);
+
+	gpiod_set_value(mt9v111->oe, 0);
+	usleep_range(500, 1000);
+
+	gpiod_set_value(mt9v111->standby, 1);
+	usleep_range(500, 1000);
+
+	clk_disable_unprepare(mt9v111->clk);
+
+	return 0;
+}
+
+static int __mt9v111_hw_reset(struct mt9v111_dev *mt9v111)
+{
+	if (!mt9v111->reset)
+		return -EINVAL;
+
+	gpiod_set_value(mt9v111->reset, 1);
+	usleep_range(500, 1000);
+
+	gpiod_set_value(mt9v111->reset, 0);
+	usleep_range(500, 1000);
+
+	return 0;
+}
+
+static int __mt9v111_sw_reset(struct mt9v111_dev *mt9v111)
+{
+	struct i2c_client *c = mt9v111->client;
+	int ret;
+
+	/* Software reset core and IFP blocks. */
+
+	ret = mt9v111_update(c, MT9V111_R01_CORE,
+			     MT9V111_CORE_R0D_CORE_RESET,
+			     MT9V111_CORE_R0D_CORE_RESET_MASK, 1);
+	if (ret)
+		return ret;
+	usleep_range(500, 1000);
+
+	ret = mt9v111_update(c, MT9V111_R01_CORE,
+			     MT9V111_CORE_R0D_CORE_RESET,
+			     MT9V111_CORE_R0D_CORE_RESET_MASK, 0);
+	if (ret)
+		return ret;
+	usleep_range(500, 1000);
+
+	ret = mt9v111_update(c, MT9V111_R01_IFP,
+			     MT9V111_IFP_R07_IFP_RESET,
+			     MT9V111_IFP_R07_IFP_RESET_MASK, 1);
+	if (ret)
+		return ret;
+	usleep_range(500, 1000);
+
+	ret = mt9v111_update(c, MT9V111_R01_IFP,
+			     MT9V111_IFP_R07_IFP_RESET,
+			     MT9V111_IFP_R07_IFP_RESET_MASK, 0);
+	if (ret)
+		return ret;
+	usleep_range(500, 1000);
+
+	return 0;
+}
+
+static int mt9v111_calc_frame_rate(struct mt9v111_dev *mt9v111,
+				   struct v4l2_fract *tpf)
+{
+	unsigned int fps = tpf->numerator ?
+			   tpf->denominator / tpf->numerator :
+			   tpf->denominator;
+	unsigned int best_diff;
+	unsigned int frm_cols;
+	unsigned int row_pclk;
+	unsigned int best_fps;
+	unsigned int pclk;
+	unsigned int diff;
+	unsigned int idx;
+	unsigned int hb;
+	unsigned int vb;
+	unsigned int i;
+	int ret;
+
+	/* Approximate to the closest supported frame interval. */
+	best_diff = ~0L;
+	for (i = 0, idx = 0; i < ARRAY_SIZE(mt9v111_frame_intervals); i++) {
+		diff = abs(fps - mt9v111_frame_intervals[i]);
+		if (diff < best_diff) {
+			idx = i;
+			best_diff = diff;
+		}
+	}
+	fps = mt9v111_frame_intervals[idx];
+
+	/*
+	 * The sensor does not provide a PLL circuitry and pixel clock is
+	 * generated dividing the master clock source by two.
+	 *
+	 * Trow = (W + Hblank + 114) * 2 * (1 / SYSCLK)
+	 * TFrame = Trow * (H + Vblank + 2)
+	 *
+	 * FPS = (SYSCLK / 2) / (Trow * (H + Vblank + 2))
+	 *
+	 * This boils down to tune H and V blanks to best approximate the
+	 * above equation.
+	 *
+	 * Test all available H/V blank values, until we reach the
+	 * desired frame rate.
+	 */
+	best_fps = vb = hb = 0;
+	pclk = DIV_ROUND_CLOSEST(mt9v111->sysclk, 2);
+	row_pclk = MT9V111_PIXEL_ARRAY_WIDTH + 7 + MT9V111_CORE_R04_WIN_H_OFFS;
+	frm_cols = MT9V111_PIXEL_ARRAY_HEIGHT + 7 + MT9V111_CORE_R03_WIN_V_OFFS;
+
+	best_diff = ~0L;
+	for (vb = MT9V111_CORE_R06_MIN_VBLANK;
+	     vb < MT9V111_CORE_R06_MAX_VBLANK; vb++) {
+		for (hb = MT9V111_CORE_R05_MIN_HBLANK;
+		     hb < MT9V111_CORE_R05_MAX_HBLANK; hb += 10) {
+			unsigned int t_frame = (row_pclk + hb) *
+					       (frm_cols + vb);
+			unsigned int t_fps = DIV_ROUND_CLOSEST(pclk, t_frame);
+
+			diff = abs(fps - t_fps);
+			if (diff < best_diff) {
+				best_diff = diff;
+				best_fps = t_fps;
+
+				if (diff == 0)
+					break;
+			}
+		}
+
+		if (diff == 0)
+			break;
+	}
+
+	ret = v4l2_ctrl_s_ctrl_int64(mt9v111->hblank, hb);
+	if (ret)
+		return ret;
+
+	ret = v4l2_ctrl_s_ctrl_int64(mt9v111->vblank, vb);
+	if (ret)
+		return ret;
+
+	tpf->numerator = 1;
+	tpf->denominator = best_fps;
+
+	return 0;
+}
+
+static int mt9v111_hw_config(struct mt9v111_dev *mt9v111)
+{
+	struct i2c_client *c = mt9v111->client;
+	unsigned int ret;
+	u16 outfmtctrl2;
+
+	/* Force device reset. */
+	ret = __mt9v111_hw_reset(mt9v111);
+	if (ret == -EINVAL)
+		ret = __mt9v111_sw_reset(mt9v111);
+	if (ret)
+		return ret;
+
+	/* Configure internal clock sample rate. */
+	ret = mt9v111->sysclk < DIV_ROUND_CLOSEST(MT9V111_MAX_CLKIN, 2) ?
+				mt9v111_update(c, MT9V111_R01_CORE,
+					MT9V111_CORE_R07_OUT_CTRL,
+					MT9V111_CORE_R07_OUT_CTRL_SAMPLE, 1) :
+				mt9v111_update(c, MT9V111_R01_CORE,
+					MT9V111_CORE_R07_OUT_CTRL,
+					MT9V111_CORE_R07_OUT_CTRL_SAMPLE, 0);
+	if (ret)
+		return ret;
+
+	/*
+	 * Configure output image format components ordering.
+	 *
+	 * TODO: IFP block can also output several RGB permutations, we only
+	 *	 support YUYV permutations at the moment.
+	 */
+	switch (mt9v111->fmt.code) {
+	case MEDIA_BUS_FMT_YUYV8_2X8:
+			outfmtctrl2 = MT9V111_IFP_R3A_OUTFMT_CTRL2_SWAP_YC;
+			break;
+	case MEDIA_BUS_FMT_VYUY8_2X8:
+			outfmtctrl2 = MT9V111_IFP_R3A_OUTFMT_CTRL2_SWAP_CBCR;
+			break;
+	case MEDIA_BUS_FMT_YVYU8_2X8:
+			outfmtctrl2 = MT9V111_IFP_R3A_OUTFMT_CTRL2_SWAP_YC |
+				      MT9V111_IFP_R3A_OUTFMT_CTRL2_SWAP_CBCR;
+			break;
+	case MEDIA_BUS_FMT_UYVY8_2X8:
+	default:
+			outfmtctrl2 = 0;
+			break;
+	}
+
+	ret = mt9v111_update(c, MT9V111_R01_IFP, MT9V111_IFP_R3A_OUTFMT_CTRL2,
+			     MT9V111_IFP_R3A_OUTFMT_CTRL2_SWAP_MASK,
+			     outfmtctrl2);
+	if (ret)
+		return ret;
+
+	/*
+	 * Do not change default sensor's core configuration:
+	 * output the whole 640x480 pixel array, skip 18 columns and 6 rows.
+	 *
+	 * Instead, control the output image size through IFP block.
+	 *
+	 * TODO: No zoom&pan support. Currently we control the output image
+	 *	 size only through decimation, with no zoom support.
+	 */
+	ret = mt9v111_write(c, MT9V111_R01_IFP, MT9V111_IFP_RA5_HPAN,
+			    MT9V111_IFP_DECIMATION_FREEZE);
+	if (ret)
+		return ret;
+
+	ret = mt9v111_write(c, MT9V111_R01_IFP, MT9V111_IFP_RA8_VPAN,
+			    MT9V111_IFP_DECIMATION_FREEZE);
+	if (ret)
+		return ret;
+
+	ret = mt9v111_write(c, MT9V111_R01_IFP, MT9V111_IFP_RA6_HZOOM,
+			    MT9V111_IFP_DECIMATION_FREEZE |
+			    MT9V111_PIXEL_ARRAY_WIDTH);
+	if (ret)
+		return ret;
+
+	ret = mt9v111_write(c, MT9V111_R01_IFP, MT9V111_IFP_RA9_VZOOM,
+			    MT9V111_IFP_DECIMATION_FREEZE |
+			    MT9V111_PIXEL_ARRAY_HEIGHT);
+	if (ret)
+		return ret;
+
+	ret = mt9v111_write(c, MT9V111_R01_IFP, MT9V111_IFP_RA7_HOUT,
+			    MT9V111_IFP_DECIMATION_FREEZE |
+			    mt9v111->fmt.width);
+	if (ret)
+		return ret;
+
+	ret = mt9v111_write(c, MT9V111_R01_IFP, MT9V111_IFP_RAA_VOUT,
+			    mt9v111->fmt.height);
+	if (ret)
+		return ret;
+
+	/* Apply controls to set auto exp, auto awb and timings */
+	ret = v4l2_ctrl_handler_setup(&mt9v111->ctrls);
+	if (ret)
+		return ret;
+
+	/*
+	 * Set pixel integration time to the whole frame time.
+	 * This value controls the the shutter delay when running with AE
+	 * disabled. If longer than frame time, it affects the output
+	 * frame rate.
+	 */
+	return mt9v111_write(c, MT9V111_R01_CORE, MT9V111_CORE_R09_PIXEL_INT,
+			     MT9V111_PIXEL_ARRAY_HEIGHT);
+}
+
+/* ---  V4L2 subdev operations --- */
+
+static int mt9v111_s_power(struct v4l2_subdev *sd, int on)
+{
+	struct mt9v111_dev *mt9v111 = sd_to_mt9v111(sd);
+	int pwr_count;
+	int ret = 0;
+
+	mutex_lock(&mt9v111->pwr_mutex);
+
+	/*
+	 * Make sure we're transitioning from 0 to 1, or viceversa,
+	 * before actually changing the power state.
+	 */
+	pwr_count = mt9v111->pwr_count;
+	pwr_count += on ? 1 : -1;
+	if (pwr_count == !!on) {
+		ret = on ? __mt9v111_power_on(sd) :
+			   __mt9v111_power_off(sd);
+		if (!ret)
+			/* All went well, updated power counter. */
+			mt9v111->pwr_count = pwr_count;
+
+		mutex_unlock(&mt9v111->pwr_mutex);
+
+		return ret;
+	}
+
+	/*
+	 * Update power counter to keep track of how many nested calls we
+	 * received.
+	 */
+	WARN_ON(pwr_count < 0 || pwr_count > 1);
+	mt9v111->pwr_count = pwr_count;
+
+	mutex_unlock(&mt9v111->pwr_mutex);
+
+	return ret;
+}
+
+static int mt9v111_s_stream(struct v4l2_subdev *subdev, int enable)
+{
+	struct mt9v111_dev *mt9v111 = sd_to_mt9v111(subdev);
+	int ret;
+
+	mutex_lock(&mt9v111->stream_mutex);
+
+	if (mt9v111->streaming == enable) {
+		mutex_unlock(&mt9v111->stream_mutex);
+		return 0;
+	}
+
+	ret = mt9v111_s_power(subdev, enable);
+	if (ret)
+		goto error_unlock;
+
+	if (enable && mt9v111->pending) {
+		ret = mt9v111_hw_config(mt9v111);
+		if (ret)
+			goto error_unlock;
+
+		/*
+		 * No need to update control here as far as only H/VBLANK are
+		 * supported and immediately programmed to registers in .s_ctrl
+		 */
+
+		mt9v111->pending = false;
+	}
+
+	mt9v111->streaming = enable ? true : false;
+	mutex_unlock(&mt9v111->stream_mutex);
+
+	return 0;
+
+error_unlock:
+	mutex_unlock(&mt9v111->stream_mutex);
+
+	return ret;
+}
+
+static int mt9v111_s_frame_interval(struct v4l2_subdev *sd,
+				    struct v4l2_subdev_frame_interval *ival)
+{
+	struct mt9v111_dev *mt9v111 = sd_to_mt9v111(sd);
+	struct v4l2_fract *tpf = &ival->interval;
+	unsigned int fps = tpf->numerator ?
+			   tpf->denominator / tpf->numerator :
+			   tpf->denominator;
+	unsigned int max_fps;
+
+	if (!tpf->numerator)
+		tpf->numerator = 1;
+
+	mutex_lock(&mt9v111->stream_mutex);
+
+	if (mt9v111->streaming) {
+		mutex_unlock(&mt9v111->stream_mutex);
+		return -EBUSY;
+	}
+
+	if (mt9v111->fps == fps) {
+		mutex_unlock(&mt9v111->stream_mutex);
+		return 0;
+	}
+
+	/* Make sure frame rate/image sizes constraints are respected. */
+	if (mt9v111->fmt.width < QVGA_WIDTH &&
+	    mt9v111->fmt.height < QVGA_HEIGHT)
+		max_fps = 90;
+	else if (mt9v111->fmt.width < CIF_WIDTH &&
+		 mt9v111->fmt.height < CIF_HEIGHT)
+		max_fps = 60;
+	else
+		max_fps = mt9v111->sysclk <
+				DIV_ROUND_CLOSEST(MT9V111_MAX_CLKIN, 2) ? 15 :
+									  30;
+
+	if (fps > max_fps) {
+		mutex_unlock(&mt9v111->stream_mutex);
+		return -EINVAL;
+	}
+
+	mt9v111_calc_frame_rate(mt9v111, tpf);
+
+	mt9v111->fps = fps;
+	mt9v111->pending = true;
+
+	mutex_unlock(&mt9v111->stream_mutex);
+
+	return 0;
+}
+
+static int mt9v111_g_frame_interval(struct v4l2_subdev *sd,
+				    struct v4l2_subdev_frame_interval *ival)
+{
+	struct mt9v111_dev *mt9v111 = sd_to_mt9v111(sd);
+	struct v4l2_fract *tpf = &ival->interval;
+
+	mutex_lock(&mt9v111->stream_mutex);
+
+	tpf->numerator = 1;
+	tpf->denominator = mt9v111->fps;
+
+	mutex_unlock(&mt9v111->stream_mutex);
+
+	return 0;
+}
+
+static struct v4l2_mbus_framefmt *__mt9v111_get_pad_format(
+					struct mt9v111_dev *mt9v111,
+					struct v4l2_subdev_pad_config *cfg,
+					unsigned int pad,
+					enum v4l2_subdev_format_whence which)
+{
+	switch (which) {
+	case V4L2_SUBDEV_FORMAT_TRY:
+#if IS_ENABLED(CONFIG_VIDEO_V4L2_SUBDEV_API)
+		return v4l2_subdev_get_try_format(&mt9v111->sd, cfg, pad);
+#else
+		return &cfg->try_fmt;
+#endif
+	case V4L2_SUBDEV_FORMAT_ACTIVE:
+		return &mt9v111->fmt;
+	default:
+		return NULL;
+	}
+}
+
+static int mt9v111_enum_mbus_code(struct v4l2_subdev *subdev,
+				  struct v4l2_subdev_pad_config *cfg,
+				  struct v4l2_subdev_mbus_code_enum *code)
+{
+	if (code->pad || code->index > ARRAY_SIZE(mt9v111_formats) - 1)
+		return -EINVAL;
+
+	code->code = mt9v111_formats[code->index].code;
+
+	return 0;
+}
+
+static int mt9v111_enum_frame_interval(struct v4l2_subdev *sd,
+				struct v4l2_subdev_pad_config *cfg,
+				struct v4l2_subdev_frame_interval_enum *fie)
+{
+	unsigned int i;
+
+	if (fie->pad || fie->index >= ARRAY_SIZE(mt9v111_frame_intervals))
+		return -EINVAL;
+
+	for (i = 0; i < ARRAY_SIZE(mt9v111_frame_sizes); i++)
+		if (fie->width == mt9v111_frame_sizes[i].width &&
+		    fie->height == mt9v111_frame_sizes[i].height)
+			break;
+
+	if (i == ARRAY_SIZE(mt9v111_frame_sizes))
+		return -EINVAL;
+
+	fie->interval.numerator = 1;
+	fie->interval.denominator = mt9v111_frame_intervals[fie->index];
+
+	return 0;
+}
+
+static int mt9v111_enum_frame_size(struct v4l2_subdev *subdev,
+				   struct v4l2_subdev_pad_config *cfg,
+				   struct v4l2_subdev_frame_size_enum *fse)
+{
+	if (fse->pad || fse->index >= ARRAY_SIZE(mt9v111_frame_sizes))
+		return -EINVAL;
+
+	fse->min_width = mt9v111_frame_sizes[fse->index].width;
+	fse->max_width = mt9v111_frame_sizes[fse->index].width;
+	fse->min_height = mt9v111_frame_sizes[fse->index].height;
+	fse->max_height = mt9v111_frame_sizes[fse->index].height;
+
+	return 0;
+}
+
+static int mt9v111_get_format(struct v4l2_subdev *subdev,
+			      struct v4l2_subdev_pad_config *cfg,
+			      struct v4l2_subdev_format *format)
+{
+	struct mt9v111_dev *mt9v111 = sd_to_mt9v111(subdev);
+
+	if (format->pad)
+		return -EINVAL;
+
+	mutex_lock(&mt9v111->stream_mutex);
+	format->format = *__mt9v111_get_pad_format(mt9v111, cfg, format->pad,
+						   format->which);
+	mutex_unlock(&mt9v111->stream_mutex);
+
+	return 0;
+}
+
+static int mt9v111_set_format(struct v4l2_subdev *subdev,
+			      struct v4l2_subdev_pad_config *cfg,
+			      struct v4l2_subdev_format *format)
+{
+	struct mt9v111_dev *mt9v111 = sd_to_mt9v111(subdev);
+	struct v4l2_mbus_framefmt new_fmt;
+	struct v4l2_mbus_framefmt *__fmt;
+	unsigned int best_fit = ~0L;
+	unsigned int idx = 0;
+	unsigned int i;
+
+	mutex_lock(&mt9v111->stream_mutex);
+	if (mt9v111->streaming) {
+		mutex_unlock(&mt9v111->stream_mutex);
+		return -EBUSY;
+	}
+
+	if (format->pad) {
+		mutex_unlock(&mt9v111->stream_mutex);
+		return -EINVAL;
+	}
+
+	/* Update mbus format code and sizes. */
+	for (i = 0; i < ARRAY_SIZE(mt9v111_formats); i++) {
+		if (format->format.code == mt9v111_formats[i].code) {
+			new_fmt.code = mt9v111_formats[i].code;
+			break;
+		}
+	}
+	if (i == ARRAY_SIZE(mt9v111_formats))
+		new_fmt.code = mt9v111_formats[0].code;
+
+	for (i = 0; i < ARRAY_SIZE(mt9v111_frame_sizes); i++) {
+		unsigned int fit = abs(mt9v111_frame_sizes[i].width -
+				       format->format.width) +
+				   abs(mt9v111_frame_sizes[i].height -
+				       format->format.height);
+		if (fit < best_fit) {
+			best_fit = fit;
+			idx = i;
+
+			if (fit == 0)
+				break;
+		}
+	}
+	new_fmt.width = mt9v111_frame_sizes[idx].width;
+	new_fmt.height = mt9v111_frame_sizes[idx].height;
+
+	/* Update the device (or pad) format if it has changed. */
+	__fmt = __mt9v111_get_pad_format(mt9v111, cfg, format->pad,
+					 format->which);
+
+	/* Format hasn't changed, stop here. */
+	if (__fmt->code == new_fmt.code &&
+	    __fmt->width == new_fmt.width &&
+	    __fmt->height == new_fmt.height)
+		goto done;
+
+	/* Update the format and sizes, then  mark changes as pending. */
+	__fmt->code = new_fmt.code;
+	__fmt->width = new_fmt.width;
+	__fmt->height = new_fmt.height;
+
+	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
+		mt9v111->pending = true;
+
+	dev_dbg(mt9v111->dev, "%s: mbus_code: %x - (%ux%u)\n",
+		__func__, __fmt->code, __fmt->width, __fmt->height);
+
+done:
+	format->format = *__fmt;
+
+	mutex_unlock(&mt9v111->stream_mutex);
+
+	return 0;
+}
+
+static int mt9v111_init_cfg(struct v4l2_subdev *subdev,
+			    struct v4l2_subdev_pad_config *cfg)
+{
+	cfg->try_fmt = mt9v111_def_fmt;
+
+	return 0;
+}
+
+static const struct v4l2_subdev_core_ops mt9v111_core_ops = {
+	.s_power		= mt9v111_s_power,
+};
+
+static const struct v4l2_subdev_video_ops mt9v111_video_ops = {
+	.s_stream		= mt9v111_s_stream,
+	.s_frame_interval	= mt9v111_s_frame_interval,
+	.g_frame_interval	= mt9v111_g_frame_interval,
+};
+
+static const struct v4l2_subdev_pad_ops mt9v111_pad_ops = {
+	.init_cfg		= mt9v111_init_cfg,
+	.enum_mbus_code		= mt9v111_enum_mbus_code,
+	.enum_frame_size	= mt9v111_enum_frame_size,
+	.enum_frame_interval	= mt9v111_enum_frame_interval,
+	.get_fmt		= mt9v111_get_format,
+	.set_fmt		= mt9v111_set_format,
+};
+
+static const struct v4l2_subdev_ops mt9v111_ops = {
+	.core	= &mt9v111_core_ops,
+	.video	= &mt9v111_video_ops,
+	.pad	= &mt9v111_pad_ops,
+};
+
+#if IS_ENABLED(CONFIG_MEDIA_CONTROLLER)
+static const struct media_entity_operations mt9v111_subdev_entity_ops = {
+	.link_validate = v4l2_subdev_link_validate,
+};
+#endif
+
+/* --- V4L2 ctrl --- */
+static int mt9v111_s_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct mt9v111_dev *mt9v111 = container_of(ctrl->handler,
+						   struct mt9v111_dev,
+						   ctrls);
+	int ret;
+
+	mutex_lock(&mt9v111->pwr_mutex);
+	/*
+	 * If sensor is powered down, just cache new control values,
+	 * no actual register access.
+	 */
+	if (!mt9v111->pwr_count) {
+		mt9v111->pending = true;
+		mutex_unlock(&mt9v111->pwr_mutex);
+		return 0;
+	}
+	mutex_unlock(&mt9v111->pwr_mutex);
+
+	/*
+	 * Flickering control gets disabled if both auto exp and auto awb
+	 * are disabled too. If any of the two is enabled, enable it.
+	 *
+	 * Disabling flickering when ae and awb are off allows a more precise
+	 * control of the programmed frame rate.
+	 */
+	if (mt9v111->auto_exp->is_new || mt9v111->auto_awb->is_new) {
+		if (mt9v111->auto_exp->val == V4L2_EXPOSURE_MANUAL &&
+		    mt9v111->auto_awb->val == V4L2_WHITE_BALANCE_MANUAL)
+			ret = mt9v111_update(mt9v111->client, MT9V111_R01_IFP,
+					     MT9V111_IFP_R08_OUTFMT_CTRL,
+					     MT9V111_IFP_R08_OUTFMT_CTRL_FLICKER,
+					     0);
+		else
+			ret = mt9v111_update(mt9v111->client, MT9V111_R01_IFP,
+					     MT9V111_IFP_R08_OUTFMT_CTRL,
+					     MT9V111_IFP_R08_OUTFMT_CTRL_FLICKER,
+					     1);
+		if (ret)
+			return ret;
+	}
+
+	ret = -EINVAL;
+	switch (ctrl->id) {
+	case V4L2_CID_AUTO_WHITE_BALANCE:
+		ret = mt9v111_update(mt9v111->client, MT9V111_R01_IFP,
+				     MT9V111_IFP_R06_OPMODE_CTRL,
+				     MT9V111_IFP_R06_OPMODE_CTRL_AWB_EN,
+				     ctrl->val == V4L2_WHITE_BALANCE_AUTO ?
+				     MT9V111_IFP_R06_OPMODE_CTRL_AWB_EN : 0);
+		break;
+	case V4L2_CID_EXPOSURE_AUTO:
+		ret = mt9v111_update(mt9v111->client, MT9V111_R01_IFP,
+				     MT9V111_IFP_R06_OPMODE_CTRL,
+				     MT9V111_IFP_R06_OPMODE_CTRL_AE_EN,
+				     ctrl->val == V4L2_EXPOSURE_AUTO ?
+				     MT9V111_IFP_R06_OPMODE_CTRL_AE_EN : 0);
+		break;
+	case V4L2_CID_HBLANK:
+		ret = mt9v111_update(mt9v111->client, MT9V111_R01_CORE,
+				     MT9V111_CORE_R05_HBLANK,
+				     MT9V111_CORE_R05_MAX_HBLANK,
+				     mt9v111->hblank->val);
+		break;
+	case V4L2_CID_VBLANK:
+		ret = mt9v111_update(mt9v111->client, MT9V111_R01_CORE,
+				     MT9V111_CORE_R06_VBLANK,
+				     MT9V111_CORE_R06_MAX_VBLANK,
+				     mt9v111->vblank->val);
+		break;
+	}
+
+	return ret;
+}
+
+static const struct v4l2_ctrl_ops mt9v111_ctrl_ops = {
+	.s_ctrl = mt9v111_s_ctrl,
+};
+
+static int mt9v111_chip_probe(struct mt9v111_dev *mt9v111)
+{
+	int ret;
+	u16 val;
+
+	ret = __mt9v111_power_on(&mt9v111->sd);
+	if (ret)
+		return ret;
+
+	ret = mt9v111_read(mt9v111->client, MT9V111_R01_CORE,
+			   MT9V111_CORE_RFF_CHIP_VER, &val);
+	if (ret)
+		goto power_off;
+
+	if ((val >> 8) != MT9V111_CHIP_ID_HIGH &&
+	    (val & 0xff) != MT9V111_CHIP_ID_LOW) {
+		dev_err(mt9v111->dev,
+			"Unable to identify MT9V111 chip: 0x%2x%2x\n",
+			val >> 8, val & 0xff);
+		ret = -EIO;
+		goto power_off;
+	}
+
+	dev_dbg(mt9v111->dev, "Chip identified: 0x%2x%2x\n",
+		val >> 8, val & 0xff);
+
+power_off:
+	__mt9v111_power_off(&mt9v111->sd);
+
+	return ret;
+}
+
+static int mt9v111_probe(struct i2c_client *client)
+{
+	struct mt9v111_dev *mt9v111;
+	struct v4l2_fract tpf;
+	int ret;
+
+	mt9v111 = devm_kzalloc(&client->dev, sizeof(*mt9v111), GFP_KERNEL);
+	if (!mt9v111)
+		return -ENOMEM;
+
+	mt9v111->dev = &client->dev;
+	mt9v111->client = client;
+
+	mt9v111->clk = devm_clk_get(&client->dev, NULL);
+	if (IS_ERR(mt9v111->clk))
+		return PTR_ERR(mt9v111->clk);
+
+	mt9v111->sysclk = clk_get_rate(mt9v111->clk);
+	if (mt9v111->sysclk > MT9V111_MAX_CLKIN)
+		return -EINVAL;
+
+	mt9v111->oe = devm_gpiod_get_optional(&client->dev, "enable",
+					      GPIOD_OUT_LOW);
+	if (IS_ERR(mt9v111->oe)) {
+		dev_err(&client->dev, "Unable to get GPIO \"enable\": %ld\n",
+			PTR_ERR(mt9v111->oe));
+		return PTR_ERR(mt9v111->oe);
+	}
+
+	mt9v111->standby = devm_gpiod_get_optional(&client->dev, "standby",
+						   GPIOD_OUT_HIGH);
+	if (IS_ERR(mt9v111->standby)) {
+		dev_err(&client->dev, "Unable to get GPIO \"standby\": %ld\n",
+			PTR_ERR(mt9v111->standby));
+		return PTR_ERR(mt9v111->standby);
+	}
+
+	mt9v111->reset = devm_gpiod_get_optional(&client->dev, "reset",
+						 GPIOD_OUT_LOW);
+	if (IS_ERR(mt9v111->reset)) {
+		dev_err(&client->dev, "Unable to get GPIO \"reset\": %ld\n",
+			PTR_ERR(mt9v111->reset));
+		return PTR_ERR(mt9v111->reset);
+	}
+
+	mutex_init(&mt9v111->pwr_mutex);
+	mutex_init(&mt9v111->stream_mutex);
+
+	v4l2_ctrl_handler_init(&mt9v111->ctrls, 5);
+
+	mt9v111->auto_awb = v4l2_ctrl_new_std(&mt9v111->ctrls,
+					      &mt9v111_ctrl_ops,
+					      V4L2_CID_AUTO_WHITE_BALANCE,
+					      0, 1, 1,
+					      V4L2_WHITE_BALANCE_AUTO);
+	mt9v111->auto_exp = v4l2_ctrl_new_std_menu(&mt9v111->ctrls,
+						   &mt9v111_ctrl_ops,
+						   V4L2_CID_EXPOSURE_AUTO,
+						   V4L2_EXPOSURE_MANUAL,
+						   0, V4L2_EXPOSURE_AUTO);
+	mt9v111->hblank = v4l2_ctrl_new_std(&mt9v111->ctrls, &mt9v111_ctrl_ops,
+					    V4L2_CID_HBLANK,
+					    MT9V111_CORE_R05_MIN_HBLANK,
+					    MT9V111_CORE_R05_MAX_HBLANK, 1,
+					    MT9V111_CORE_R05_DEF_HBLANK);
+	mt9v111->vblank = v4l2_ctrl_new_std(&mt9v111->ctrls, &mt9v111_ctrl_ops,
+					    V4L2_CID_VBLANK,
+					    MT9V111_CORE_R06_MIN_VBLANK,
+					    MT9V111_CORE_R06_MAX_VBLANK, 1,
+					    MT9V111_CORE_R06_DEF_VBLANK);
+
+	/* PIXEL_RATE is fixed: just expose it to user space. */
+	v4l2_ctrl_new_std(&mt9v111->ctrls, &mt9v111_ctrl_ops,
+			  V4L2_CID_PIXEL_RATE, 0,
+			  DIV_ROUND_CLOSEST(mt9v111->sysclk, 2), 1,
+			  DIV_ROUND_CLOSEST(mt9v111->sysclk, 2));
+
+	if (mt9v111->ctrls.error) {
+		ret = mt9v111->ctrls.error;
+		goto error_free_ctrls;
+	}
+	mt9v111->sd.ctrl_handler = &mt9v111->ctrls;
+
+	/* Start with default configuration: 640x480 UYVY. */
+	mt9v111->fmt	= mt9v111_def_fmt;
+
+	/* Re-calculate blankings for 640x480@15fps. */
+	mt9v111->fps		= 15;
+	tpf.numerator		= 1;
+	tpf.denominator		= mt9v111->fps;
+	mt9v111_calc_frame_rate(mt9v111, &tpf);
+
+	mt9v111->pwr_count	= 0;
+	mt9v111->addr_space	= MT9V111_R01_IFP;
+	mt9v111->pending	= true;
+
+	v4l2_i2c_subdev_init(&mt9v111->sd, client, &mt9v111_ops);
+
+#if IS_ENABLED(CONFIG_MEDIA_CONTROLLER)
+	mt9v111->sd.flags	|= V4L2_SUBDEV_FL_HAS_DEVNODE;
+	mt9v111->sd.entity.ops	= &mt9v111_subdev_entity_ops;
+	mt9v111->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
+
+	mt9v111->pad.flags	= MEDIA_PAD_FL_SOURCE;
+	ret = media_entity_pads_init(&mt9v111->sd.entity, 1, &mt9v111->pad);
+	if (ret)
+		goto error_free_entity;
+#endif
+
+	ret = mt9v111_chip_probe(mt9v111);
+	if (ret)
+		goto error_free_entity;
+
+	ret = v4l2_async_register_subdev(&mt9v111->sd);
+	if (ret)
+		goto error_free_entity;
+
+	return 0;
+
+error_free_entity:
+#if IS_ENABLED(CONFIG_MEDIA_CONTROLLER)
+	media_entity_cleanup(&mt9v111->sd.entity);
+#endif
+
+error_free_ctrls:
+	v4l2_ctrl_handler_free(&mt9v111->ctrls);
+
+	mutex_destroy(&mt9v111->pwr_mutex);
+	mutex_destroy(&mt9v111->stream_mutex);
+
+	return ret;
+}
+
+static int mt9v111_remove(struct i2c_client *client)
+{
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct mt9v111_dev *mt9v111 = sd_to_mt9v111(sd);
+
+	v4l2_async_unregister_subdev(sd);
+
+#if IS_ENABLED(CONFIG_MEDIA_CONTROLLER)
+	media_entity_cleanup(&sd->entity);
+#endif
+
+	v4l2_ctrl_handler_free(&mt9v111->ctrls);
+
+	mutex_destroy(&mt9v111->pwr_mutex);
+	mutex_destroy(&mt9v111->stream_mutex);
+
+	devm_gpiod_put(mt9v111->dev, mt9v111->oe);
+	devm_gpiod_put(mt9v111->dev, mt9v111->standby);
+	devm_gpiod_put(mt9v111->dev, mt9v111->reset);
+
+	devm_clk_put(mt9v111->dev, mt9v111->clk);
+
+	return 0;
+}
+
+static const struct of_device_id mt9v111_of_match[] = {
+	{ .compatible = "aptina,mt9v111", },
+	{ /* sentinel */ },
+};
+
+static struct i2c_driver mt9v111_driver = {
+	.driver = {
+		.name = "mt9v111",
+		.of_match_table = mt9v111_of_match,
+	},
+	.probe_new	= mt9v111_probe,
+	.remove		= mt9v111_remove,
+};
+
+module_i2c_driver(mt9v111_driver);
+
+MODULE_DESCRIPTION("V4L2 sensor driver for Aptina MT9V111");
+MODULE_AUTHOR("Jacopo Mondi <jacopo@jmondi.org>");
+MODULE_LICENSE("GPL v2");