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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lm3646.c (10772B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * drivers/media/i2c/lm3646.c
      4 * General device driver for TI lm3646, Dual FLASH LED Driver
      5 *
      6 * Copyright (C) 2014 Texas Instruments
      7 *
      8 * Contact: Daniel Jeong <gshark.jeong@gmail.com>
      9 *			Ldd-Mlp <ldd-mlp@list.ti.com>
     10 */
     11
     12#include <linux/delay.h>
     13#include <linux/i2c.h>
     14#include <linux/module.h>
     15#include <linux/slab.h>
     16#include <linux/regmap.h>
     17#include <linux/videodev2.h>
     18#include <media/i2c/lm3646.h>
     19#include <media/v4l2-ctrls.h>
     20#include <media/v4l2-device.h>
     21
     22/* registers definitions */
     23#define REG_ENABLE		0x01
     24#define REG_TORCH_BR	0x05
     25#define REG_FLASH_BR	0x05
     26#define REG_FLASH_TOUT	0x04
     27#define REG_FLAG		0x08
     28#define REG_STROBE_SRC	0x06
     29#define REG_LED1_FLASH_BR 0x06
     30#define REG_LED1_TORCH_BR 0x07
     31
     32#define MASK_ENABLE		0x03
     33#define MASK_TORCH_BR	0x70
     34#define MASK_FLASH_BR	0x0F
     35#define MASK_FLASH_TOUT	0x07
     36#define MASK_FLAG		0xFF
     37#define MASK_STROBE_SRC	0x80
     38
     39/* Fault Mask */
     40#define FAULT_TIMEOUT	(1<<0)
     41#define FAULT_SHORT_CIRCUIT	(1<<1)
     42#define FAULT_UVLO		(1<<2)
     43#define FAULT_IVFM		(1<<3)
     44#define FAULT_OCP		(1<<4)
     45#define FAULT_OVERTEMP	(1<<5)
     46#define FAULT_NTC_TRIP	(1<<6)
     47#define FAULT_OVP		(1<<7)
     48
     49enum led_mode {
     50	MODE_SHDN = 0x0,
     51	MODE_TORCH = 0x2,
     52	MODE_FLASH = 0x3,
     53};
     54
     55/*
     56 * struct lm3646_flash
     57 *
     58 * @pdata: platform data
     59 * @regmap: reg. map for i2c
     60 * @lock: muxtex for serial access.
     61 * @led_mode: V4L2 LED mode
     62 * @ctrls_led: V4L2 controls
     63 * @subdev_led: V4L2 subdev
     64 * @mode_reg : mode register value
     65 */
     66struct lm3646_flash {
     67	struct device *dev;
     68	struct lm3646_platform_data *pdata;
     69	struct regmap *regmap;
     70
     71	struct v4l2_ctrl_handler ctrls_led;
     72	struct v4l2_subdev subdev_led;
     73
     74	u8 mode_reg;
     75};
     76
     77#define to_lm3646_flash(_ctrl)	\
     78	container_of(_ctrl->handler, struct lm3646_flash, ctrls_led)
     79
     80/* enable mode control */
     81static int lm3646_mode_ctrl(struct lm3646_flash *flash,
     82			    enum v4l2_flash_led_mode led_mode)
     83{
     84	switch (led_mode) {
     85	case V4L2_FLASH_LED_MODE_NONE:
     86		return regmap_write(flash->regmap,
     87				    REG_ENABLE, flash->mode_reg | MODE_SHDN);
     88	case V4L2_FLASH_LED_MODE_TORCH:
     89		return regmap_write(flash->regmap,
     90				    REG_ENABLE, flash->mode_reg | MODE_TORCH);
     91	case V4L2_FLASH_LED_MODE_FLASH:
     92		return regmap_write(flash->regmap,
     93				    REG_ENABLE, flash->mode_reg | MODE_FLASH);
     94	}
     95	return -EINVAL;
     96}
     97
     98/* V4L2 controls  */
     99static int lm3646_get_ctrl(struct v4l2_ctrl *ctrl)
    100{
    101	struct lm3646_flash *flash = to_lm3646_flash(ctrl);
    102	unsigned int reg_val;
    103	int rval;
    104
    105	if (ctrl->id != V4L2_CID_FLASH_FAULT)
    106		return -EINVAL;
    107
    108	rval = regmap_read(flash->regmap, REG_FLAG, &reg_val);
    109	if (rval < 0)
    110		return rval;
    111
    112	ctrl->val = 0;
    113	if (reg_val & FAULT_TIMEOUT)
    114		ctrl->val |= V4L2_FLASH_FAULT_TIMEOUT;
    115	if (reg_val & FAULT_SHORT_CIRCUIT)
    116		ctrl->val |= V4L2_FLASH_FAULT_SHORT_CIRCUIT;
    117	if (reg_val & FAULT_UVLO)
    118		ctrl->val |= V4L2_FLASH_FAULT_UNDER_VOLTAGE;
    119	if (reg_val & FAULT_IVFM)
    120		ctrl->val |= V4L2_FLASH_FAULT_INPUT_VOLTAGE;
    121	if (reg_val & FAULT_OCP)
    122		ctrl->val |= V4L2_FLASH_FAULT_OVER_CURRENT;
    123	if (reg_val & FAULT_OVERTEMP)
    124		ctrl->val |= V4L2_FLASH_FAULT_OVER_TEMPERATURE;
    125	if (reg_val & FAULT_NTC_TRIP)
    126		ctrl->val |= V4L2_FLASH_FAULT_LED_OVER_TEMPERATURE;
    127	if (reg_val & FAULT_OVP)
    128		ctrl->val |= V4L2_FLASH_FAULT_OVER_VOLTAGE;
    129
    130	return 0;
    131}
    132
    133static int lm3646_set_ctrl(struct v4l2_ctrl *ctrl)
    134{
    135	struct lm3646_flash *flash = to_lm3646_flash(ctrl);
    136	unsigned int reg_val;
    137	int rval;
    138
    139	switch (ctrl->id) {
    140	case V4L2_CID_FLASH_LED_MODE:
    141
    142		if (ctrl->val != V4L2_FLASH_LED_MODE_FLASH)
    143			return lm3646_mode_ctrl(flash, ctrl->val);
    144		/* switch to SHDN mode before flash strobe on */
    145		return lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_NONE);
    146
    147	case V4L2_CID_FLASH_STROBE_SOURCE:
    148		return regmap_update_bits(flash->regmap,
    149					  REG_STROBE_SRC, MASK_STROBE_SRC,
    150					  (ctrl->val) << 7);
    151
    152	case V4L2_CID_FLASH_STROBE:
    153
    154		/* read and check current mode of chip to start flash */
    155		rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
    156		if (rval < 0 || ((reg_val & MASK_ENABLE) != MODE_SHDN))
    157			return rval;
    158		/* flash on */
    159		return lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_FLASH);
    160
    161	case V4L2_CID_FLASH_STROBE_STOP:
    162
    163		/*
    164		 * flash mode will be turned automatically
    165		 * from FLASH mode to SHDN mode after flash duration timeout
    166		 * read and check current mode of chip to stop flash
    167		 */
    168		rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
    169		if (rval < 0)
    170			return rval;
    171		if ((reg_val & MASK_ENABLE) == MODE_FLASH)
    172			return lm3646_mode_ctrl(flash,
    173						V4L2_FLASH_LED_MODE_NONE);
    174		return rval;
    175
    176	case V4L2_CID_FLASH_TIMEOUT:
    177		return regmap_update_bits(flash->regmap,
    178					  REG_FLASH_TOUT, MASK_FLASH_TOUT,
    179					  LM3646_FLASH_TOUT_ms_TO_REG
    180					  (ctrl->val));
    181
    182	case V4L2_CID_FLASH_INTENSITY:
    183		return regmap_update_bits(flash->regmap,
    184					  REG_FLASH_BR, MASK_FLASH_BR,
    185					  LM3646_TOTAL_FLASH_BRT_uA_TO_REG
    186					  (ctrl->val));
    187
    188	case V4L2_CID_FLASH_TORCH_INTENSITY:
    189		return regmap_update_bits(flash->regmap,
    190					  REG_TORCH_BR, MASK_TORCH_BR,
    191					  LM3646_TOTAL_TORCH_BRT_uA_TO_REG
    192					  (ctrl->val) << 4);
    193	}
    194
    195	return -EINVAL;
    196}
    197
    198static const struct v4l2_ctrl_ops lm3646_led_ctrl_ops = {
    199	.g_volatile_ctrl = lm3646_get_ctrl,
    200	.s_ctrl = lm3646_set_ctrl,
    201};
    202
    203static int lm3646_init_controls(struct lm3646_flash *flash)
    204{
    205	struct v4l2_ctrl *fault;
    206	struct v4l2_ctrl_handler *hdl = &flash->ctrls_led;
    207	const struct v4l2_ctrl_ops *ops = &lm3646_led_ctrl_ops;
    208
    209	v4l2_ctrl_handler_init(hdl, 8);
    210	/* flash mode */
    211	v4l2_ctrl_new_std_menu(hdl, ops, V4L2_CID_FLASH_LED_MODE,
    212			       V4L2_FLASH_LED_MODE_TORCH, ~0x7,
    213			       V4L2_FLASH_LED_MODE_NONE);
    214
    215	/* flash source */
    216	v4l2_ctrl_new_std_menu(hdl, ops, V4L2_CID_FLASH_STROBE_SOURCE,
    217			       0x1, ~0x3, V4L2_FLASH_STROBE_SOURCE_SOFTWARE);
    218
    219	/* flash strobe */
    220	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_STROBE, 0, 0, 0, 0);
    221	/* flash strobe stop */
    222	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_STROBE_STOP, 0, 0, 0, 0);
    223
    224	/* flash strobe timeout */
    225	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_TIMEOUT,
    226			  LM3646_FLASH_TOUT_MIN,
    227			  LM3646_FLASH_TOUT_MAX,
    228			  LM3646_FLASH_TOUT_STEP, flash->pdata->flash_timeout);
    229
    230	/* max flash current */
    231	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_INTENSITY,
    232			  LM3646_TOTAL_FLASH_BRT_MIN,
    233			  LM3646_TOTAL_FLASH_BRT_MAX,
    234			  LM3646_TOTAL_FLASH_BRT_STEP,
    235			  LM3646_TOTAL_FLASH_BRT_MAX);
    236
    237	/* max torch current */
    238	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_TORCH_INTENSITY,
    239			  LM3646_TOTAL_TORCH_BRT_MIN,
    240			  LM3646_TOTAL_TORCH_BRT_MAX,
    241			  LM3646_TOTAL_TORCH_BRT_STEP,
    242			  LM3646_TOTAL_TORCH_BRT_MAX);
    243
    244	/* fault */
    245	fault = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_FAULT, 0,
    246				  V4L2_FLASH_FAULT_OVER_VOLTAGE
    247				  | V4L2_FLASH_FAULT_OVER_TEMPERATURE
    248				  | V4L2_FLASH_FAULT_SHORT_CIRCUIT
    249				  | V4L2_FLASH_FAULT_TIMEOUT, 0, 0);
    250	if (fault != NULL)
    251		fault->flags |= V4L2_CTRL_FLAG_VOLATILE;
    252
    253	if (hdl->error)
    254		return hdl->error;
    255
    256	flash->subdev_led.ctrl_handler = hdl;
    257	return 0;
    258}
    259
    260/* initialize device */
    261static const struct v4l2_subdev_ops lm3646_ops = {
    262	.core = NULL,
    263};
    264
    265static const struct regmap_config lm3646_regmap = {
    266	.reg_bits = 8,
    267	.val_bits = 8,
    268	.max_register = 0xFF,
    269};
    270
    271static int lm3646_subdev_init(struct lm3646_flash *flash)
    272{
    273	struct i2c_client *client = to_i2c_client(flash->dev);
    274	int rval;
    275
    276	v4l2_i2c_subdev_init(&flash->subdev_led, client, &lm3646_ops);
    277	flash->subdev_led.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
    278	strscpy(flash->subdev_led.name, LM3646_NAME,
    279		sizeof(flash->subdev_led.name));
    280	rval = lm3646_init_controls(flash);
    281	if (rval)
    282		goto err_out;
    283	rval = media_entity_pads_init(&flash->subdev_led.entity, 0, NULL);
    284	if (rval < 0)
    285		goto err_out;
    286	flash->subdev_led.entity.function = MEDIA_ENT_F_FLASH;
    287	return rval;
    288
    289err_out:
    290	v4l2_ctrl_handler_free(&flash->ctrls_led);
    291	return rval;
    292}
    293
    294static int lm3646_init_device(struct lm3646_flash *flash)
    295{
    296	unsigned int reg_val;
    297	int rval;
    298
    299	/* read the value of mode register to reduce redundant i2c accesses */
    300	rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
    301	if (rval < 0)
    302		return rval;
    303	flash->mode_reg = reg_val & 0xfc;
    304
    305	/* output disable */
    306	rval = lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_NONE);
    307	if (rval < 0)
    308		return rval;
    309
    310	/*
    311	 * LED1 flash current setting
    312	 * LED2 flash current = Total(Max) flash current - LED1 flash current
    313	 */
    314	rval = regmap_update_bits(flash->regmap,
    315				  REG_LED1_FLASH_BR, 0x7F,
    316				  LM3646_LED1_FLASH_BRT_uA_TO_REG
    317				  (flash->pdata->led1_flash_brt));
    318
    319	if (rval < 0)
    320		return rval;
    321
    322	/*
    323	 * LED1 torch current setting
    324	 * LED2 torch current = Total(Max) torch current - LED1 torch current
    325	 */
    326	rval = regmap_update_bits(flash->regmap,
    327				  REG_LED1_TORCH_BR, 0x7F,
    328				  LM3646_LED1_TORCH_BRT_uA_TO_REG
    329				  (flash->pdata->led1_torch_brt));
    330	if (rval < 0)
    331		return rval;
    332
    333	/* Reset flag register */
    334	return regmap_read(flash->regmap, REG_FLAG, &reg_val);
    335}
    336
    337static int lm3646_probe(struct i2c_client *client,
    338			const struct i2c_device_id *devid)
    339{
    340	struct lm3646_flash *flash;
    341	struct lm3646_platform_data *pdata = dev_get_platdata(&client->dev);
    342	int rval;
    343
    344	flash = devm_kzalloc(&client->dev, sizeof(*flash), GFP_KERNEL);
    345	if (flash == NULL)
    346		return -ENOMEM;
    347
    348	flash->regmap = devm_regmap_init_i2c(client, &lm3646_regmap);
    349	if (IS_ERR(flash->regmap))
    350		return PTR_ERR(flash->regmap);
    351
    352	/* check device tree if there is no platform data */
    353	if (pdata == NULL) {
    354		pdata = devm_kzalloc(&client->dev,
    355				     sizeof(struct lm3646_platform_data),
    356				     GFP_KERNEL);
    357		if (pdata == NULL)
    358			return -ENOMEM;
    359		/* use default data in case of no platform data */
    360		pdata->flash_timeout = LM3646_FLASH_TOUT_MAX;
    361		pdata->led1_torch_brt = LM3646_LED1_TORCH_BRT_MAX;
    362		pdata->led1_flash_brt = LM3646_LED1_FLASH_BRT_MAX;
    363	}
    364	flash->pdata = pdata;
    365	flash->dev = &client->dev;
    366
    367	rval = lm3646_subdev_init(flash);
    368	if (rval < 0)
    369		return rval;
    370
    371	rval = lm3646_init_device(flash);
    372	if (rval < 0)
    373		return rval;
    374
    375	i2c_set_clientdata(client, flash);
    376
    377	return 0;
    378}
    379
    380static int lm3646_remove(struct i2c_client *client)
    381{
    382	struct lm3646_flash *flash = i2c_get_clientdata(client);
    383
    384	v4l2_device_unregister_subdev(&flash->subdev_led);
    385	v4l2_ctrl_handler_free(&flash->ctrls_led);
    386	media_entity_cleanup(&flash->subdev_led.entity);
    387
    388	return 0;
    389}
    390
    391static const struct i2c_device_id lm3646_id_table[] = {
    392	{LM3646_NAME, 0},
    393	{}
    394};
    395
    396MODULE_DEVICE_TABLE(i2c, lm3646_id_table);
    397
    398static struct i2c_driver lm3646_i2c_driver = {
    399	.driver = {
    400		   .name = LM3646_NAME,
    401		   },
    402	.probe = lm3646_probe,
    403	.remove = lm3646_remove,
    404	.id_table = lm3646_id_table,
    405};
    406
    407module_i2c_driver(lm3646_i2c_driver);
    408
    409MODULE_AUTHOR("Daniel Jeong <gshark.jeong@gmail.com>");
    410MODULE_AUTHOR("Ldd Mlp <ldd-mlp@list.ti.com>");
    411MODULE_DESCRIPTION("Texas Instruments LM3646 Dual Flash LED driver");
    412MODULE_LICENSE("GPL");