cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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ov2740.c (29478B)


      1// SPDX-License-Identifier: GPL-2.0
      2// Copyright (c) 2020 Intel Corporation.
      3
      4#include <asm/unaligned.h>
      5#include <linux/acpi.h>
      6#include <linux/delay.h>
      7#include <linux/i2c.h>
      8#include <linux/module.h>
      9#include <linux/pm_runtime.h>
     10#include <linux/nvmem-provider.h>
     11#include <linux/regmap.h>
     12#include <media/v4l2-ctrls.h>
     13#include <media/v4l2-device.h>
     14#include <media/v4l2-fwnode.h>
     15
     16#define OV2740_LINK_FREQ_360MHZ		360000000ULL
     17#define OV2740_SCLK			72000000LL
     18#define OV2740_MCLK			19200000
     19#define OV2740_DATA_LANES		2
     20#define OV2740_RGB_DEPTH		10
     21
     22#define OV2740_REG_CHIP_ID		0x300a
     23#define OV2740_CHIP_ID			0x2740
     24
     25#define OV2740_REG_MODE_SELECT		0x0100
     26#define OV2740_MODE_STANDBY		0x00
     27#define OV2740_MODE_STREAMING		0x01
     28
     29/* vertical-timings from sensor */
     30#define OV2740_REG_VTS			0x380e
     31#define OV2740_VTS_DEF			0x088a
     32#define OV2740_VTS_MIN			0x0460
     33#define OV2740_VTS_MAX			0x7fff
     34
     35/* horizontal-timings from sensor */
     36#define OV2740_REG_HTS			0x380c
     37
     38/* Exposure controls from sensor */
     39#define OV2740_REG_EXPOSURE		0x3500
     40#define OV2740_EXPOSURE_MIN		4
     41#define OV2740_EXPOSURE_MAX_MARGIN	8
     42#define OV2740_EXPOSURE_STEP		1
     43
     44/* Analog gain controls from sensor */
     45#define OV2740_REG_ANALOG_GAIN		0x3508
     46#define OV2740_ANAL_GAIN_MIN		128
     47#define OV2740_ANAL_GAIN_MAX		1983
     48#define OV2740_ANAL_GAIN_STEP		1
     49
     50/* Digital gain controls from sensor */
     51#define OV2740_REG_MWB_R_GAIN		0x500a
     52#define OV2740_REG_MWB_G_GAIN		0x500c
     53#define OV2740_REG_MWB_B_GAIN		0x500e
     54#define OV2740_DGTL_GAIN_MIN		1024
     55#define OV2740_DGTL_GAIN_MAX		4095
     56#define OV2740_DGTL_GAIN_STEP		1
     57#define OV2740_DGTL_GAIN_DEFAULT	1024
     58
     59/* Test Pattern Control */
     60#define OV2740_REG_TEST_PATTERN		0x5040
     61#define OV2740_TEST_PATTERN_ENABLE	BIT(7)
     62#define OV2740_TEST_PATTERN_BAR_SHIFT	2
     63
     64/* Group Access */
     65#define OV2740_REG_GROUP_ACCESS		0x3208
     66#define OV2740_GROUP_HOLD_START		0x0
     67#define OV2740_GROUP_HOLD_END		0x10
     68#define OV2740_GROUP_HOLD_LAUNCH	0xa0
     69
     70/* ISP CTRL00 */
     71#define OV2740_REG_ISP_CTRL00		0x5000
     72/* ISP CTRL01 */
     73#define OV2740_REG_ISP_CTRL01		0x5001
     74/* Customer Addresses: 0x7010 - 0x710F */
     75#define CUSTOMER_USE_OTP_SIZE		0x100
     76/* OTP registers from sensor */
     77#define OV2740_REG_OTP_CUSTOMER		0x7010
     78
     79struct nvm_data {
     80	struct i2c_client *client;
     81	struct nvmem_device *nvmem;
     82	struct regmap *regmap;
     83	char *nvm_buffer;
     84};
     85
     86enum {
     87	OV2740_LINK_FREQ_360MHZ_INDEX,
     88};
     89
     90struct ov2740_reg {
     91	u16 address;
     92	u8 val;
     93};
     94
     95struct ov2740_reg_list {
     96	u32 num_of_regs;
     97	const struct ov2740_reg *regs;
     98};
     99
    100struct ov2740_link_freq_config {
    101	const struct ov2740_reg_list reg_list;
    102};
    103
    104struct ov2740_mode {
    105	/* Frame width in pixels */
    106	u32 width;
    107
    108	/* Frame height in pixels */
    109	u32 height;
    110
    111	/* Horizontal timining size */
    112	u32 hts;
    113
    114	/* Default vertical timining size */
    115	u32 vts_def;
    116
    117	/* Min vertical timining size */
    118	u32 vts_min;
    119
    120	/* Link frequency needed for this resolution */
    121	u32 link_freq_index;
    122
    123	/* Sensor register settings for this resolution */
    124	const struct ov2740_reg_list reg_list;
    125};
    126
    127static const struct ov2740_reg mipi_data_rate_720mbps[] = {
    128	{0x0103, 0x01},
    129	{0x0302, 0x4b},
    130	{0x030d, 0x4b},
    131	{0x030e, 0x02},
    132	{0x030a, 0x01},
    133	{0x0312, 0x11},
    134};
    135
    136static const struct ov2740_reg mode_1932x1092_regs[] = {
    137	{0x3000, 0x00},
    138	{0x3018, 0x32},
    139	{0x3031, 0x0a},
    140	{0x3080, 0x08},
    141	{0x3083, 0xB4},
    142	{0x3103, 0x00},
    143	{0x3104, 0x01},
    144	{0x3106, 0x01},
    145	{0x3500, 0x00},
    146	{0x3501, 0x44},
    147	{0x3502, 0x40},
    148	{0x3503, 0x88},
    149	{0x3507, 0x00},
    150	{0x3508, 0x00},
    151	{0x3509, 0x80},
    152	{0x350c, 0x00},
    153	{0x350d, 0x80},
    154	{0x3510, 0x00},
    155	{0x3511, 0x00},
    156	{0x3512, 0x20},
    157	{0x3632, 0x00},
    158	{0x3633, 0x10},
    159	{0x3634, 0x10},
    160	{0x3635, 0x10},
    161	{0x3645, 0x13},
    162	{0x3646, 0x81},
    163	{0x3636, 0x10},
    164	{0x3651, 0x0a},
    165	{0x3656, 0x02},
    166	{0x3659, 0x04},
    167	{0x365a, 0xda},
    168	{0x365b, 0xa2},
    169	{0x365c, 0x04},
    170	{0x365d, 0x1d},
    171	{0x365e, 0x1a},
    172	{0x3662, 0xd7},
    173	{0x3667, 0x78},
    174	{0x3669, 0x0a},
    175	{0x366a, 0x92},
    176	{0x3700, 0x54},
    177	{0x3702, 0x10},
    178	{0x3706, 0x42},
    179	{0x3709, 0x30},
    180	{0x370b, 0xc2},
    181	{0x3714, 0x63},
    182	{0x3715, 0x01},
    183	{0x3716, 0x00},
    184	{0x371a, 0x3e},
    185	{0x3732, 0x0e},
    186	{0x3733, 0x10},
    187	{0x375f, 0x0e},
    188	{0x3768, 0x30},
    189	{0x3769, 0x44},
    190	{0x376a, 0x22},
    191	{0x377b, 0x20},
    192	{0x377c, 0x00},
    193	{0x377d, 0x0c},
    194	{0x3798, 0x00},
    195	{0x37a1, 0x55},
    196	{0x37a8, 0x6d},
    197	{0x37c2, 0x04},
    198	{0x37c5, 0x00},
    199	{0x37c8, 0x00},
    200	{0x3800, 0x00},
    201	{0x3801, 0x00},
    202	{0x3802, 0x00},
    203	{0x3803, 0x00},
    204	{0x3804, 0x07},
    205	{0x3805, 0x8f},
    206	{0x3806, 0x04},
    207	{0x3807, 0x47},
    208	{0x3808, 0x07},
    209	{0x3809, 0x88},
    210	{0x380a, 0x04},
    211	{0x380b, 0x40},
    212	{0x380c, 0x04},
    213	{0x380d, 0x38},
    214	{0x380e, 0x04},
    215	{0x380f, 0x60},
    216	{0x3810, 0x00},
    217	{0x3811, 0x04},
    218	{0x3812, 0x00},
    219	{0x3813, 0x04},
    220	{0x3814, 0x01},
    221	{0x3815, 0x01},
    222	{0x3820, 0x80},
    223	{0x3821, 0x46},
    224	{0x3822, 0x84},
    225	{0x3829, 0x00},
    226	{0x382a, 0x01},
    227	{0x382b, 0x01},
    228	{0x3830, 0x04},
    229	{0x3836, 0x01},
    230	{0x3837, 0x08},
    231	{0x3839, 0x01},
    232	{0x383a, 0x00},
    233	{0x383b, 0x08},
    234	{0x383c, 0x00},
    235	{0x3f0b, 0x00},
    236	{0x4001, 0x20},
    237	{0x4009, 0x07},
    238	{0x4003, 0x10},
    239	{0x4010, 0xe0},
    240	{0x4016, 0x00},
    241	{0x4017, 0x10},
    242	{0x4044, 0x02},
    243	{0x4304, 0x08},
    244	{0x4307, 0x30},
    245	{0x4320, 0x80},
    246	{0x4322, 0x00},
    247	{0x4323, 0x00},
    248	{0x4324, 0x00},
    249	{0x4325, 0x00},
    250	{0x4326, 0x00},
    251	{0x4327, 0x00},
    252	{0x4328, 0x00},
    253	{0x4329, 0x00},
    254	{0x432c, 0x03},
    255	{0x432d, 0x81},
    256	{0x4501, 0x84},
    257	{0x4502, 0x40},
    258	{0x4503, 0x18},
    259	{0x4504, 0x04},
    260	{0x4508, 0x02},
    261	{0x4601, 0x10},
    262	{0x4800, 0x00},
    263	{0x4816, 0x52},
    264	{0x4837, 0x16},
    265	{0x5000, 0x7f},
    266	{0x5001, 0x00},
    267	{0x5005, 0x38},
    268	{0x501e, 0x0d},
    269	{0x5040, 0x00},
    270	{0x5901, 0x00},
    271	{0x3800, 0x00},
    272	{0x3801, 0x00},
    273	{0x3802, 0x00},
    274	{0x3803, 0x00},
    275	{0x3804, 0x07},
    276	{0x3805, 0x8f},
    277	{0x3806, 0x04},
    278	{0x3807, 0x47},
    279	{0x3808, 0x07},
    280	{0x3809, 0x8c},
    281	{0x380a, 0x04},
    282	{0x380b, 0x44},
    283	{0x3810, 0x00},
    284	{0x3811, 0x00},
    285	{0x3812, 0x00},
    286	{0x3813, 0x01},
    287};
    288
    289static const char * const ov2740_test_pattern_menu[] = {
    290	"Disabled",
    291	"Color Bar",
    292	"Top-Bottom Darker Color Bar",
    293	"Right-Left Darker Color Bar",
    294	"Bottom-Top Darker Color Bar",
    295};
    296
    297static const s64 link_freq_menu_items[] = {
    298	OV2740_LINK_FREQ_360MHZ,
    299};
    300
    301static const struct ov2740_link_freq_config link_freq_configs[] = {
    302	[OV2740_LINK_FREQ_360MHZ_INDEX] = {
    303		.reg_list = {
    304			.num_of_regs = ARRAY_SIZE(mipi_data_rate_720mbps),
    305			.regs = mipi_data_rate_720mbps,
    306		}
    307	},
    308};
    309
    310static const struct ov2740_mode supported_modes[] = {
    311	{
    312		.width = 1932,
    313		.height = 1092,
    314		.hts = 1080,
    315		.vts_def = OV2740_VTS_DEF,
    316		.vts_min = OV2740_VTS_MIN,
    317		.reg_list = {
    318			.num_of_regs = ARRAY_SIZE(mode_1932x1092_regs),
    319			.regs = mode_1932x1092_regs,
    320		},
    321		.link_freq_index = OV2740_LINK_FREQ_360MHZ_INDEX,
    322	},
    323};
    324
    325struct ov2740 {
    326	struct v4l2_subdev sd;
    327	struct media_pad pad;
    328	struct v4l2_ctrl_handler ctrl_handler;
    329
    330	/* V4L2 Controls */
    331	struct v4l2_ctrl *link_freq;
    332	struct v4l2_ctrl *pixel_rate;
    333	struct v4l2_ctrl *vblank;
    334	struct v4l2_ctrl *hblank;
    335	struct v4l2_ctrl *exposure;
    336
    337	/* Current mode */
    338	const struct ov2740_mode *cur_mode;
    339
    340	/* To serialize asynchronus callbacks */
    341	struct mutex mutex;
    342
    343	/* Streaming on/off */
    344	bool streaming;
    345
    346	/* NVM data inforamtion */
    347	struct nvm_data *nvm;
    348
    349	/* True if the device has been identified */
    350	bool identified;
    351};
    352
    353static inline struct ov2740 *to_ov2740(struct v4l2_subdev *subdev)
    354{
    355	return container_of(subdev, struct ov2740, sd);
    356}
    357
    358static u64 to_pixel_rate(u32 f_index)
    359{
    360	u64 pixel_rate = link_freq_menu_items[f_index] * 2 * OV2740_DATA_LANES;
    361
    362	do_div(pixel_rate, OV2740_RGB_DEPTH);
    363
    364	return pixel_rate;
    365}
    366
    367static u64 to_pixels_per_line(u32 hts, u32 f_index)
    368{
    369	u64 ppl = hts * to_pixel_rate(f_index);
    370
    371	do_div(ppl, OV2740_SCLK);
    372
    373	return ppl;
    374}
    375
    376static int ov2740_read_reg(struct ov2740 *ov2740, u16 reg, u16 len, u32 *val)
    377{
    378	struct i2c_client *client = v4l2_get_subdevdata(&ov2740->sd);
    379	struct i2c_msg msgs[2];
    380	u8 addr_buf[2];
    381	u8 data_buf[4] = {0};
    382	int ret = 0;
    383
    384	if (len > sizeof(data_buf))
    385		return -EINVAL;
    386
    387	put_unaligned_be16(reg, addr_buf);
    388	msgs[0].addr = client->addr;
    389	msgs[0].flags = 0;
    390	msgs[0].len = sizeof(addr_buf);
    391	msgs[0].buf = addr_buf;
    392	msgs[1].addr = client->addr;
    393	msgs[1].flags = I2C_M_RD;
    394	msgs[1].len = len;
    395	msgs[1].buf = &data_buf[sizeof(data_buf) - len];
    396
    397	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
    398	if (ret != ARRAY_SIZE(msgs))
    399		return ret < 0 ? ret : -EIO;
    400
    401	*val = get_unaligned_be32(data_buf);
    402
    403	return 0;
    404}
    405
    406static int ov2740_write_reg(struct ov2740 *ov2740, u16 reg, u16 len, u32 val)
    407{
    408	struct i2c_client *client = v4l2_get_subdevdata(&ov2740->sd);
    409	u8 buf[6];
    410	int ret = 0;
    411
    412	if (len > 4)
    413		return -EINVAL;
    414
    415	put_unaligned_be16(reg, buf);
    416	put_unaligned_be32(val << 8 * (4 - len), buf + 2);
    417
    418	ret = i2c_master_send(client, buf, len + 2);
    419	if (ret != len + 2)
    420		return ret < 0 ? ret : -EIO;
    421
    422	return 0;
    423}
    424
    425static int ov2740_write_reg_list(struct ov2740 *ov2740,
    426				 const struct ov2740_reg_list *r_list)
    427{
    428	struct i2c_client *client = v4l2_get_subdevdata(&ov2740->sd);
    429	unsigned int i;
    430	int ret = 0;
    431
    432	for (i = 0; i < r_list->num_of_regs; i++) {
    433		ret = ov2740_write_reg(ov2740, r_list->regs[i].address, 1,
    434				       r_list->regs[i].val);
    435		if (ret) {
    436			dev_err_ratelimited(&client->dev,
    437					    "write reg 0x%4.4x return err = %d",
    438					    r_list->regs[i].address, ret);
    439			return ret;
    440		}
    441	}
    442
    443	return 0;
    444}
    445
    446static int ov2740_identify_module(struct ov2740 *ov2740)
    447{
    448	struct i2c_client *client = v4l2_get_subdevdata(&ov2740->sd);
    449	int ret;
    450	u32 val;
    451
    452	if (ov2740->identified)
    453		return 0;
    454
    455	ret = ov2740_read_reg(ov2740, OV2740_REG_CHIP_ID, 3, &val);
    456	if (ret)
    457		return ret;
    458
    459	if (val != OV2740_CHIP_ID) {
    460		dev_err(&client->dev, "chip id mismatch: %x!=%x",
    461			OV2740_CHIP_ID, val);
    462		return -ENXIO;
    463	}
    464
    465	ov2740->identified = true;
    466
    467	return 0;
    468}
    469
    470static int ov2740_update_digital_gain(struct ov2740 *ov2740, u32 d_gain)
    471{
    472	int ret = 0;
    473
    474	ret = ov2740_write_reg(ov2740, OV2740_REG_GROUP_ACCESS, 1,
    475			       OV2740_GROUP_HOLD_START);
    476	if (ret)
    477		return ret;
    478
    479	ret = ov2740_write_reg(ov2740, OV2740_REG_MWB_R_GAIN, 2, d_gain);
    480	if (ret)
    481		return ret;
    482
    483	ret = ov2740_write_reg(ov2740, OV2740_REG_MWB_G_GAIN, 2, d_gain);
    484	if (ret)
    485		return ret;
    486
    487	ret = ov2740_write_reg(ov2740, OV2740_REG_MWB_B_GAIN, 2, d_gain);
    488	if (ret)
    489		return ret;
    490
    491	ret = ov2740_write_reg(ov2740, OV2740_REG_GROUP_ACCESS, 1,
    492			       OV2740_GROUP_HOLD_END);
    493	if (ret)
    494		return ret;
    495
    496	ret = ov2740_write_reg(ov2740, OV2740_REG_GROUP_ACCESS, 1,
    497			       OV2740_GROUP_HOLD_LAUNCH);
    498	return ret;
    499}
    500
    501static int ov2740_test_pattern(struct ov2740 *ov2740, u32 pattern)
    502{
    503	if (pattern)
    504		pattern = (pattern - 1) << OV2740_TEST_PATTERN_BAR_SHIFT |
    505			  OV2740_TEST_PATTERN_ENABLE;
    506
    507	return ov2740_write_reg(ov2740, OV2740_REG_TEST_PATTERN, 1, pattern);
    508}
    509
    510static int ov2740_set_ctrl(struct v4l2_ctrl *ctrl)
    511{
    512	struct ov2740 *ov2740 = container_of(ctrl->handler,
    513					     struct ov2740, ctrl_handler);
    514	struct i2c_client *client = v4l2_get_subdevdata(&ov2740->sd);
    515	s64 exposure_max;
    516	int ret = 0;
    517
    518	/* Propagate change of current control to all related controls */
    519	if (ctrl->id == V4L2_CID_VBLANK) {
    520		/* Update max exposure while meeting expected vblanking */
    521		exposure_max = ov2740->cur_mode->height + ctrl->val -
    522			       OV2740_EXPOSURE_MAX_MARGIN;
    523		__v4l2_ctrl_modify_range(ov2740->exposure,
    524					 ov2740->exposure->minimum,
    525					 exposure_max, ov2740->exposure->step,
    526					 exposure_max);
    527	}
    528
    529	/* V4L2 controls values will be applied only when power is already up */
    530	if (!pm_runtime_get_if_in_use(&client->dev))
    531		return 0;
    532
    533	switch (ctrl->id) {
    534	case V4L2_CID_ANALOGUE_GAIN:
    535		ret = ov2740_write_reg(ov2740, OV2740_REG_ANALOG_GAIN, 2,
    536				       ctrl->val);
    537		break;
    538
    539	case V4L2_CID_DIGITAL_GAIN:
    540		ret = ov2740_update_digital_gain(ov2740, ctrl->val);
    541		break;
    542
    543	case V4L2_CID_EXPOSURE:
    544		/* 4 least significant bits of expsoure are fractional part */
    545		ret = ov2740_write_reg(ov2740, OV2740_REG_EXPOSURE, 3,
    546				       ctrl->val << 4);
    547		break;
    548
    549	case V4L2_CID_VBLANK:
    550		ret = ov2740_write_reg(ov2740, OV2740_REG_VTS, 2,
    551				       ov2740->cur_mode->height + ctrl->val);
    552		break;
    553
    554	case V4L2_CID_TEST_PATTERN:
    555		ret = ov2740_test_pattern(ov2740, ctrl->val);
    556		break;
    557
    558	default:
    559		ret = -EINVAL;
    560		break;
    561	}
    562
    563	pm_runtime_put(&client->dev);
    564
    565	return ret;
    566}
    567
    568static const struct v4l2_ctrl_ops ov2740_ctrl_ops = {
    569	.s_ctrl = ov2740_set_ctrl,
    570};
    571
    572static int ov2740_init_controls(struct ov2740 *ov2740)
    573{
    574	struct v4l2_ctrl_handler *ctrl_hdlr;
    575	const struct ov2740_mode *cur_mode;
    576	s64 exposure_max, h_blank, pixel_rate;
    577	u32 vblank_min, vblank_max, vblank_default;
    578	int size;
    579	int ret = 0;
    580
    581	ctrl_hdlr = &ov2740->ctrl_handler;
    582	ret = v4l2_ctrl_handler_init(ctrl_hdlr, 8);
    583	if (ret)
    584		return ret;
    585
    586	ctrl_hdlr->lock = &ov2740->mutex;
    587	cur_mode = ov2740->cur_mode;
    588	size = ARRAY_SIZE(link_freq_menu_items);
    589
    590	ov2740->link_freq = v4l2_ctrl_new_int_menu(ctrl_hdlr, &ov2740_ctrl_ops,
    591						   V4L2_CID_LINK_FREQ,
    592						   size - 1, 0,
    593						   link_freq_menu_items);
    594	if (ov2740->link_freq)
    595		ov2740->link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;
    596
    597	pixel_rate = to_pixel_rate(OV2740_LINK_FREQ_360MHZ_INDEX);
    598	ov2740->pixel_rate = v4l2_ctrl_new_std(ctrl_hdlr, &ov2740_ctrl_ops,
    599					       V4L2_CID_PIXEL_RATE, 0,
    600					       pixel_rate, 1, pixel_rate);
    601
    602	vblank_min = cur_mode->vts_min - cur_mode->height;
    603	vblank_max = OV2740_VTS_MAX - cur_mode->height;
    604	vblank_default = cur_mode->vts_def - cur_mode->height;
    605	ov2740->vblank = v4l2_ctrl_new_std(ctrl_hdlr, &ov2740_ctrl_ops,
    606					   V4L2_CID_VBLANK, vblank_min,
    607					   vblank_max, 1, vblank_default);
    608
    609	h_blank = to_pixels_per_line(cur_mode->hts, cur_mode->link_freq_index);
    610	h_blank -= cur_mode->width;
    611	ov2740->hblank = v4l2_ctrl_new_std(ctrl_hdlr, &ov2740_ctrl_ops,
    612					   V4L2_CID_HBLANK, h_blank, h_blank, 1,
    613					   h_blank);
    614	if (ov2740->hblank)
    615		ov2740->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
    616
    617	v4l2_ctrl_new_std(ctrl_hdlr, &ov2740_ctrl_ops, V4L2_CID_ANALOGUE_GAIN,
    618			  OV2740_ANAL_GAIN_MIN, OV2740_ANAL_GAIN_MAX,
    619			  OV2740_ANAL_GAIN_STEP, OV2740_ANAL_GAIN_MIN);
    620	v4l2_ctrl_new_std(ctrl_hdlr, &ov2740_ctrl_ops, V4L2_CID_DIGITAL_GAIN,
    621			  OV2740_DGTL_GAIN_MIN, OV2740_DGTL_GAIN_MAX,
    622			  OV2740_DGTL_GAIN_STEP, OV2740_DGTL_GAIN_DEFAULT);
    623	exposure_max = cur_mode->vts_def - OV2740_EXPOSURE_MAX_MARGIN;
    624	ov2740->exposure = v4l2_ctrl_new_std(ctrl_hdlr, &ov2740_ctrl_ops,
    625					     V4L2_CID_EXPOSURE,
    626					     OV2740_EXPOSURE_MIN, exposure_max,
    627					     OV2740_EXPOSURE_STEP,
    628					     exposure_max);
    629	v4l2_ctrl_new_std_menu_items(ctrl_hdlr, &ov2740_ctrl_ops,
    630				     V4L2_CID_TEST_PATTERN,
    631				     ARRAY_SIZE(ov2740_test_pattern_menu) - 1,
    632				     0, 0, ov2740_test_pattern_menu);
    633	if (ctrl_hdlr->error)
    634		return ctrl_hdlr->error;
    635
    636	ov2740->sd.ctrl_handler = ctrl_hdlr;
    637
    638	return 0;
    639}
    640
    641static void ov2740_update_pad_format(const struct ov2740_mode *mode,
    642				     struct v4l2_mbus_framefmt *fmt)
    643{
    644	fmt->width = mode->width;
    645	fmt->height = mode->height;
    646	fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
    647	fmt->field = V4L2_FIELD_NONE;
    648}
    649
    650static int ov2740_load_otp_data(struct nvm_data *nvm)
    651{
    652	struct i2c_client *client;
    653	struct ov2740 *ov2740;
    654	u32 isp_ctrl00 = 0;
    655	u32 isp_ctrl01 = 0;
    656	int ret;
    657
    658	if (!nvm)
    659		return -EINVAL;
    660
    661	if (nvm->nvm_buffer)
    662		return 0;
    663
    664	client = nvm->client;
    665	ov2740 = to_ov2740(i2c_get_clientdata(client));
    666
    667	nvm->nvm_buffer = kzalloc(CUSTOMER_USE_OTP_SIZE, GFP_KERNEL);
    668	if (!nvm->nvm_buffer)
    669		return -ENOMEM;
    670
    671	ret = ov2740_read_reg(ov2740, OV2740_REG_ISP_CTRL00, 1, &isp_ctrl00);
    672	if (ret) {
    673		dev_err(&client->dev, "failed to read ISP CTRL00\n");
    674		goto err;
    675	}
    676
    677	ret = ov2740_read_reg(ov2740, OV2740_REG_ISP_CTRL01, 1, &isp_ctrl01);
    678	if (ret) {
    679		dev_err(&client->dev, "failed to read ISP CTRL01\n");
    680		goto err;
    681	}
    682
    683	/* Clear bit 5 of ISP CTRL00 */
    684	ret = ov2740_write_reg(ov2740, OV2740_REG_ISP_CTRL00, 1,
    685			       isp_ctrl00 & ~BIT(5));
    686	if (ret) {
    687		dev_err(&client->dev, "failed to set ISP CTRL00\n");
    688		goto err;
    689	}
    690
    691	/* Clear bit 7 of ISP CTRL01 */
    692	ret = ov2740_write_reg(ov2740, OV2740_REG_ISP_CTRL01, 1,
    693			       isp_ctrl01 & ~BIT(7));
    694	if (ret) {
    695		dev_err(&client->dev, "failed to set ISP CTRL01\n");
    696		goto err;
    697	}
    698
    699	ret = ov2740_write_reg(ov2740, OV2740_REG_MODE_SELECT, 1,
    700			       OV2740_MODE_STREAMING);
    701	if (ret) {
    702		dev_err(&client->dev, "failed to set streaming mode\n");
    703		goto err;
    704	}
    705
    706	/*
    707	 * Users are not allowed to access OTP-related registers and memory
    708	 * during the 20 ms period after streaming starts (0x100 = 0x01).
    709	 */
    710	msleep(20);
    711
    712	ret = regmap_bulk_read(nvm->regmap, OV2740_REG_OTP_CUSTOMER,
    713			       nvm->nvm_buffer, CUSTOMER_USE_OTP_SIZE);
    714	if (ret) {
    715		dev_err(&client->dev, "failed to read OTP data, ret %d\n", ret);
    716		goto err;
    717	}
    718
    719	ret = ov2740_write_reg(ov2740, OV2740_REG_MODE_SELECT, 1,
    720			       OV2740_MODE_STANDBY);
    721	if (ret) {
    722		dev_err(&client->dev, "failed to set streaming mode\n");
    723		goto err;
    724	}
    725
    726	ret = ov2740_write_reg(ov2740, OV2740_REG_ISP_CTRL01, 1, isp_ctrl01);
    727	if (ret) {
    728		dev_err(&client->dev, "failed to set ISP CTRL01\n");
    729		goto err;
    730	}
    731
    732	ret = ov2740_write_reg(ov2740, OV2740_REG_ISP_CTRL00, 1, isp_ctrl00);
    733	if (ret) {
    734		dev_err(&client->dev, "failed to set ISP CTRL00\n");
    735		goto err;
    736	}
    737
    738	return 0;
    739err:
    740	kfree(nvm->nvm_buffer);
    741	nvm->nvm_buffer = NULL;
    742
    743	return ret;
    744}
    745
    746static int ov2740_start_streaming(struct ov2740 *ov2740)
    747{
    748	struct i2c_client *client = v4l2_get_subdevdata(&ov2740->sd);
    749	struct nvm_data *nvm = ov2740->nvm;
    750	const struct ov2740_reg_list *reg_list;
    751	int link_freq_index;
    752	int ret = 0;
    753
    754	ret = ov2740_identify_module(ov2740);
    755	if (ret)
    756		return ret;
    757
    758	ov2740_load_otp_data(nvm);
    759
    760	link_freq_index = ov2740->cur_mode->link_freq_index;
    761	reg_list = &link_freq_configs[link_freq_index].reg_list;
    762	ret = ov2740_write_reg_list(ov2740, reg_list);
    763	if (ret) {
    764		dev_err(&client->dev, "failed to set plls");
    765		return ret;
    766	}
    767
    768	reg_list = &ov2740->cur_mode->reg_list;
    769	ret = ov2740_write_reg_list(ov2740, reg_list);
    770	if (ret) {
    771		dev_err(&client->dev, "failed to set mode");
    772		return ret;
    773	}
    774
    775	ret = __v4l2_ctrl_handler_setup(ov2740->sd.ctrl_handler);
    776	if (ret)
    777		return ret;
    778
    779	ret = ov2740_write_reg(ov2740, OV2740_REG_MODE_SELECT, 1,
    780			       OV2740_MODE_STREAMING);
    781	if (ret)
    782		dev_err(&client->dev, "failed to start streaming");
    783
    784	return ret;
    785}
    786
    787static void ov2740_stop_streaming(struct ov2740 *ov2740)
    788{
    789	struct i2c_client *client = v4l2_get_subdevdata(&ov2740->sd);
    790
    791	if (ov2740_write_reg(ov2740, OV2740_REG_MODE_SELECT, 1,
    792			     OV2740_MODE_STANDBY))
    793		dev_err(&client->dev, "failed to stop streaming");
    794}
    795
    796static int ov2740_set_stream(struct v4l2_subdev *sd, int enable)
    797{
    798	struct ov2740 *ov2740 = to_ov2740(sd);
    799	struct i2c_client *client = v4l2_get_subdevdata(sd);
    800	int ret = 0;
    801
    802	if (ov2740->streaming == enable)
    803		return 0;
    804
    805	mutex_lock(&ov2740->mutex);
    806	if (enable) {
    807		ret = pm_runtime_resume_and_get(&client->dev);
    808		if (ret < 0) {
    809			mutex_unlock(&ov2740->mutex);
    810			return ret;
    811		}
    812
    813		ret = ov2740_start_streaming(ov2740);
    814		if (ret) {
    815			enable = 0;
    816			ov2740_stop_streaming(ov2740);
    817			pm_runtime_put(&client->dev);
    818		}
    819	} else {
    820		ov2740_stop_streaming(ov2740);
    821		pm_runtime_put(&client->dev);
    822	}
    823
    824	ov2740->streaming = enable;
    825	mutex_unlock(&ov2740->mutex);
    826
    827	return ret;
    828}
    829
    830static int __maybe_unused ov2740_suspend(struct device *dev)
    831{
    832	struct v4l2_subdev *sd = dev_get_drvdata(dev);
    833	struct ov2740 *ov2740 = to_ov2740(sd);
    834
    835	mutex_lock(&ov2740->mutex);
    836	if (ov2740->streaming)
    837		ov2740_stop_streaming(ov2740);
    838
    839	mutex_unlock(&ov2740->mutex);
    840
    841	return 0;
    842}
    843
    844static int __maybe_unused ov2740_resume(struct device *dev)
    845{
    846	struct v4l2_subdev *sd = dev_get_drvdata(dev);
    847	struct ov2740 *ov2740 = to_ov2740(sd);
    848	int ret = 0;
    849
    850	mutex_lock(&ov2740->mutex);
    851	if (!ov2740->streaming)
    852		goto exit;
    853
    854	ret = ov2740_start_streaming(ov2740);
    855	if (ret) {
    856		ov2740->streaming = false;
    857		ov2740_stop_streaming(ov2740);
    858	}
    859
    860exit:
    861	mutex_unlock(&ov2740->mutex);
    862	return ret;
    863}
    864
    865static int ov2740_set_format(struct v4l2_subdev *sd,
    866			     struct v4l2_subdev_state *sd_state,
    867			     struct v4l2_subdev_format *fmt)
    868{
    869	struct ov2740 *ov2740 = to_ov2740(sd);
    870	const struct ov2740_mode *mode;
    871	s32 vblank_def, h_blank;
    872
    873	mode = v4l2_find_nearest_size(supported_modes,
    874				      ARRAY_SIZE(supported_modes), width,
    875				      height, fmt->format.width,
    876				      fmt->format.height);
    877
    878	mutex_lock(&ov2740->mutex);
    879	ov2740_update_pad_format(mode, &fmt->format);
    880	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
    881		*v4l2_subdev_get_try_format(sd, sd_state, fmt->pad) = fmt->format;
    882	} else {
    883		ov2740->cur_mode = mode;
    884		__v4l2_ctrl_s_ctrl(ov2740->link_freq, mode->link_freq_index);
    885		__v4l2_ctrl_s_ctrl_int64(ov2740->pixel_rate,
    886					 to_pixel_rate(mode->link_freq_index));
    887
    888		/* Update limits and set FPS to default */
    889		vblank_def = mode->vts_def - mode->height;
    890		__v4l2_ctrl_modify_range(ov2740->vblank,
    891					 mode->vts_min - mode->height,
    892					 OV2740_VTS_MAX - mode->height, 1,
    893					 vblank_def);
    894		__v4l2_ctrl_s_ctrl(ov2740->vblank, vblank_def);
    895		h_blank = to_pixels_per_line(mode->hts, mode->link_freq_index) -
    896			  mode->width;
    897		__v4l2_ctrl_modify_range(ov2740->hblank, h_blank, h_blank, 1,
    898					 h_blank);
    899	}
    900	mutex_unlock(&ov2740->mutex);
    901
    902	return 0;
    903}
    904
    905static int ov2740_get_format(struct v4l2_subdev *sd,
    906			     struct v4l2_subdev_state *sd_state,
    907			     struct v4l2_subdev_format *fmt)
    908{
    909	struct ov2740 *ov2740 = to_ov2740(sd);
    910
    911	mutex_lock(&ov2740->mutex);
    912	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
    913		fmt->format = *v4l2_subdev_get_try_format(&ov2740->sd,
    914							  sd_state,
    915							  fmt->pad);
    916	else
    917		ov2740_update_pad_format(ov2740->cur_mode, &fmt->format);
    918
    919	mutex_unlock(&ov2740->mutex);
    920
    921	return 0;
    922}
    923
    924static int ov2740_enum_mbus_code(struct v4l2_subdev *sd,
    925				 struct v4l2_subdev_state *sd_state,
    926				 struct v4l2_subdev_mbus_code_enum *code)
    927{
    928	if (code->index > 0)
    929		return -EINVAL;
    930
    931	code->code = MEDIA_BUS_FMT_SGRBG10_1X10;
    932
    933	return 0;
    934}
    935
    936static int ov2740_enum_frame_size(struct v4l2_subdev *sd,
    937				  struct v4l2_subdev_state *sd_state,
    938				  struct v4l2_subdev_frame_size_enum *fse)
    939{
    940	if (fse->index >= ARRAY_SIZE(supported_modes))
    941		return -EINVAL;
    942
    943	if (fse->code != MEDIA_BUS_FMT_SGRBG10_1X10)
    944		return -EINVAL;
    945
    946	fse->min_width = supported_modes[fse->index].width;
    947	fse->max_width = fse->min_width;
    948	fse->min_height = supported_modes[fse->index].height;
    949	fse->max_height = fse->min_height;
    950
    951	return 0;
    952}
    953
    954static int ov2740_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
    955{
    956	struct ov2740 *ov2740 = to_ov2740(sd);
    957
    958	mutex_lock(&ov2740->mutex);
    959	ov2740_update_pad_format(&supported_modes[0],
    960				 v4l2_subdev_get_try_format(sd, fh->state, 0));
    961	mutex_unlock(&ov2740->mutex);
    962
    963	return 0;
    964}
    965
    966static const struct v4l2_subdev_video_ops ov2740_video_ops = {
    967	.s_stream = ov2740_set_stream,
    968};
    969
    970static const struct v4l2_subdev_pad_ops ov2740_pad_ops = {
    971	.set_fmt = ov2740_set_format,
    972	.get_fmt = ov2740_get_format,
    973	.enum_mbus_code = ov2740_enum_mbus_code,
    974	.enum_frame_size = ov2740_enum_frame_size,
    975};
    976
    977static const struct v4l2_subdev_ops ov2740_subdev_ops = {
    978	.video = &ov2740_video_ops,
    979	.pad = &ov2740_pad_ops,
    980};
    981
    982static const struct media_entity_operations ov2740_subdev_entity_ops = {
    983	.link_validate = v4l2_subdev_link_validate,
    984};
    985
    986static const struct v4l2_subdev_internal_ops ov2740_internal_ops = {
    987	.open = ov2740_open,
    988};
    989
    990static int ov2740_check_hwcfg(struct device *dev)
    991{
    992	struct fwnode_handle *ep;
    993	struct fwnode_handle *fwnode = dev_fwnode(dev);
    994	struct v4l2_fwnode_endpoint bus_cfg = {
    995		.bus_type = V4L2_MBUS_CSI2_DPHY
    996	};
    997	u32 mclk;
    998	int ret;
    999	unsigned int i, j;
   1000
   1001	if (!fwnode)
   1002		return -ENXIO;
   1003
   1004	ret = fwnode_property_read_u32(fwnode, "clock-frequency", &mclk);
   1005	if (ret)
   1006		return ret;
   1007
   1008	if (mclk != OV2740_MCLK) {
   1009		dev_err(dev, "external clock %d is not supported", mclk);
   1010		return -EINVAL;
   1011	}
   1012
   1013	ep = fwnode_graph_get_next_endpoint(fwnode, NULL);
   1014	if (!ep)
   1015		return -ENXIO;
   1016
   1017	ret = v4l2_fwnode_endpoint_alloc_parse(ep, &bus_cfg);
   1018	fwnode_handle_put(ep);
   1019	if (ret)
   1020		return ret;
   1021
   1022	if (bus_cfg.bus.mipi_csi2.num_data_lanes != OV2740_DATA_LANES) {
   1023		dev_err(dev, "number of CSI2 data lanes %d is not supported",
   1024			bus_cfg.bus.mipi_csi2.num_data_lanes);
   1025		ret = -EINVAL;
   1026		goto check_hwcfg_error;
   1027	}
   1028
   1029	if (!bus_cfg.nr_of_link_frequencies) {
   1030		dev_err(dev, "no link frequencies defined");
   1031		ret = -EINVAL;
   1032		goto check_hwcfg_error;
   1033	}
   1034
   1035	for (i = 0; i < ARRAY_SIZE(link_freq_menu_items); i++) {
   1036		for (j = 0; j < bus_cfg.nr_of_link_frequencies; j++) {
   1037			if (link_freq_menu_items[i] ==
   1038				bus_cfg.link_frequencies[j])
   1039				break;
   1040		}
   1041
   1042		if (j == bus_cfg.nr_of_link_frequencies) {
   1043			dev_err(dev, "no link frequency %lld supported",
   1044				link_freq_menu_items[i]);
   1045			ret = -EINVAL;
   1046			goto check_hwcfg_error;
   1047		}
   1048	}
   1049
   1050check_hwcfg_error:
   1051	v4l2_fwnode_endpoint_free(&bus_cfg);
   1052
   1053	return ret;
   1054}
   1055
   1056static int ov2740_remove(struct i2c_client *client)
   1057{
   1058	struct v4l2_subdev *sd = i2c_get_clientdata(client);
   1059	struct ov2740 *ov2740 = to_ov2740(sd);
   1060
   1061	v4l2_async_unregister_subdev(sd);
   1062	media_entity_cleanup(&sd->entity);
   1063	v4l2_ctrl_handler_free(sd->ctrl_handler);
   1064	pm_runtime_disable(&client->dev);
   1065	mutex_destroy(&ov2740->mutex);
   1066
   1067	return 0;
   1068}
   1069
   1070static int ov2740_nvmem_read(void *priv, unsigned int off, void *val,
   1071			     size_t count)
   1072{
   1073	struct nvm_data *nvm = priv;
   1074	struct v4l2_subdev *sd = i2c_get_clientdata(nvm->client);
   1075	struct device *dev = &nvm->client->dev;
   1076	struct ov2740 *ov2740 = to_ov2740(sd);
   1077	int ret = 0;
   1078
   1079	mutex_lock(&ov2740->mutex);
   1080
   1081	if (nvm->nvm_buffer) {
   1082		memcpy(val, nvm->nvm_buffer + off, count);
   1083		goto exit;
   1084	}
   1085
   1086	ret = pm_runtime_resume_and_get(dev);
   1087	if (ret < 0) {
   1088		goto exit;
   1089	}
   1090
   1091	ret = ov2740_load_otp_data(nvm);
   1092	if (!ret)
   1093		memcpy(val, nvm->nvm_buffer + off, count);
   1094
   1095	pm_runtime_put(dev);
   1096exit:
   1097	mutex_unlock(&ov2740->mutex);
   1098	return ret;
   1099}
   1100
   1101static int ov2740_register_nvmem(struct i2c_client *client,
   1102				 struct ov2740 *ov2740)
   1103{
   1104	struct nvm_data *nvm;
   1105	struct regmap_config regmap_config = { };
   1106	struct nvmem_config nvmem_config = { };
   1107	struct regmap *regmap;
   1108	struct device *dev = &client->dev;
   1109	int ret;
   1110
   1111	nvm = devm_kzalloc(dev, sizeof(*nvm), GFP_KERNEL);
   1112	if (!nvm)
   1113		return -ENOMEM;
   1114
   1115	regmap_config.val_bits = 8;
   1116	regmap_config.reg_bits = 16;
   1117	regmap_config.disable_locking = true;
   1118	regmap = devm_regmap_init_i2c(client, &regmap_config);
   1119	if (IS_ERR(regmap))
   1120		return PTR_ERR(regmap);
   1121
   1122	nvm->regmap = regmap;
   1123	nvm->client = client;
   1124
   1125	nvmem_config.name = dev_name(dev);
   1126	nvmem_config.dev = dev;
   1127	nvmem_config.read_only = true;
   1128	nvmem_config.root_only = true;
   1129	nvmem_config.owner = THIS_MODULE;
   1130	nvmem_config.compat = true;
   1131	nvmem_config.base_dev = dev;
   1132	nvmem_config.reg_read = ov2740_nvmem_read;
   1133	nvmem_config.reg_write = NULL;
   1134	nvmem_config.priv = nvm;
   1135	nvmem_config.stride = 1;
   1136	nvmem_config.word_size = 1;
   1137	nvmem_config.size = CUSTOMER_USE_OTP_SIZE;
   1138
   1139	nvm->nvmem = devm_nvmem_register(dev, &nvmem_config);
   1140
   1141	ret = PTR_ERR_OR_ZERO(nvm->nvmem);
   1142	if (!ret)
   1143		ov2740->nvm = nvm;
   1144
   1145	return ret;
   1146}
   1147
   1148static int ov2740_probe(struct i2c_client *client)
   1149{
   1150	struct ov2740 *ov2740;
   1151	int ret = 0;
   1152	bool full_power;
   1153
   1154	ret = ov2740_check_hwcfg(&client->dev);
   1155	if (ret) {
   1156		dev_err(&client->dev, "failed to check HW configuration: %d",
   1157			ret);
   1158		return ret;
   1159	}
   1160
   1161	ov2740 = devm_kzalloc(&client->dev, sizeof(*ov2740), GFP_KERNEL);
   1162	if (!ov2740)
   1163		return -ENOMEM;
   1164
   1165	v4l2_i2c_subdev_init(&ov2740->sd, client, &ov2740_subdev_ops);
   1166	full_power = acpi_dev_state_d0(&client->dev);
   1167	if (full_power) {
   1168		ret = ov2740_identify_module(ov2740);
   1169		if (ret) {
   1170			dev_err(&client->dev, "failed to find sensor: %d", ret);
   1171			return ret;
   1172		}
   1173	}
   1174
   1175	mutex_init(&ov2740->mutex);
   1176	ov2740->cur_mode = &supported_modes[0];
   1177	ret = ov2740_init_controls(ov2740);
   1178	if (ret) {
   1179		dev_err(&client->dev, "failed to init controls: %d", ret);
   1180		goto probe_error_v4l2_ctrl_handler_free;
   1181	}
   1182
   1183	ov2740->sd.internal_ops = &ov2740_internal_ops;
   1184	ov2740->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
   1185	ov2740->sd.entity.ops = &ov2740_subdev_entity_ops;
   1186	ov2740->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
   1187	ov2740->pad.flags = MEDIA_PAD_FL_SOURCE;
   1188	ret = media_entity_pads_init(&ov2740->sd.entity, 1, &ov2740->pad);
   1189	if (ret) {
   1190		dev_err(&client->dev, "failed to init entity pads: %d", ret);
   1191		goto probe_error_v4l2_ctrl_handler_free;
   1192	}
   1193
   1194	ret = v4l2_async_register_subdev_sensor(&ov2740->sd);
   1195	if (ret < 0) {
   1196		dev_err(&client->dev, "failed to register V4L2 subdev: %d",
   1197			ret);
   1198		goto probe_error_media_entity_cleanup;
   1199	}
   1200
   1201	ret = ov2740_register_nvmem(client, ov2740);
   1202	if (ret)
   1203		dev_warn(&client->dev, "register nvmem failed, ret %d\n", ret);
   1204
   1205	/* Set the device's state to active if it's in D0 state. */
   1206	if (full_power)
   1207		pm_runtime_set_active(&client->dev);
   1208	pm_runtime_enable(&client->dev);
   1209	pm_runtime_idle(&client->dev);
   1210
   1211	return 0;
   1212
   1213probe_error_media_entity_cleanup:
   1214	media_entity_cleanup(&ov2740->sd.entity);
   1215
   1216probe_error_v4l2_ctrl_handler_free:
   1217	v4l2_ctrl_handler_free(ov2740->sd.ctrl_handler);
   1218	mutex_destroy(&ov2740->mutex);
   1219
   1220	return ret;
   1221}
   1222
   1223static const struct dev_pm_ops ov2740_pm_ops = {
   1224	SET_SYSTEM_SLEEP_PM_OPS(ov2740_suspend, ov2740_resume)
   1225};
   1226
   1227static const struct acpi_device_id ov2740_acpi_ids[] = {
   1228	{"INT3474"},
   1229	{}
   1230};
   1231
   1232MODULE_DEVICE_TABLE(acpi, ov2740_acpi_ids);
   1233
   1234static struct i2c_driver ov2740_i2c_driver = {
   1235	.driver = {
   1236		.name = "ov2740",
   1237		.pm = &ov2740_pm_ops,
   1238		.acpi_match_table = ov2740_acpi_ids,
   1239	},
   1240	.probe_new = ov2740_probe,
   1241	.remove = ov2740_remove,
   1242	.flags = I2C_DRV_ACPI_WAIVE_D0_PROBE,
   1243};
   1244
   1245module_i2c_driver(ov2740_i2c_driver);
   1246
   1247MODULE_AUTHOR("Qiu, Tianshu <tian.shu.qiu@intel.com>");
   1248MODULE_AUTHOR("Shawn Tu <shawnx.tu@intel.com>");
   1249MODULE_AUTHOR("Bingbu Cao <bingbu.cao@intel.com>");
   1250MODULE_DESCRIPTION("OmniVision OV2740 sensor driver");
   1251MODULE_LICENSE("GPL v2");