leds-pca955x.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright 2007-2008 Extreme Engineering Solutions, Inc.
  4 *
  5 * Author: Nate Case <ncase@xes-inc.com>
  6 *
  7 * LED driver for various PCA955x I2C LED drivers
  8 *
  9 * Supported devices:
 10 *
 11 *	Device		Description		7-bit slave address
 12 *	------		-----------		-------------------
 13 *	PCA9550		2-bit driver		0x60 .. 0x61
 14 *	PCA9551		8-bit driver		0x60 .. 0x67
 15 *	PCA9552		16-bit driver		0x60 .. 0x67
 16 *	PCA9553/01	4-bit driver		0x62
 17 *	PCA9553/02	4-bit driver		0x63
 18 *
 19 * Philips PCA955x LED driver chips follow a register map as shown below:
 20 *
 21 *	Control Register		Description
 22 *	----------------		-----------
 23 *	0x0				Input register 0
 24 *					..
 25 *	NUM_INPUT_REGS - 1		Last Input register X
 26 *
 27 *	NUM_INPUT_REGS			Frequency prescaler 0
 28 *	NUM_INPUT_REGS + 1		PWM register 0
 29 *	NUM_INPUT_REGS + 2		Frequency prescaler 1
 30 *	NUM_INPUT_REGS + 3		PWM register 1
 31 *
 32 *	NUM_INPUT_REGS + 4		LED selector 0
 33 *	NUM_INPUT_REGS + 4
 34 *	    + NUM_LED_REGS - 1		Last LED selector
 35 *
 36 *  where NUM_INPUT_REGS and NUM_LED_REGS vary depending on how many
 37 *  bits the chip supports.
 38 */
 39
 40#include <linux/bitops.h>
 41#include <linux/ctype.h>
 42#include <linux/delay.h>
 43#include <linux/err.h>
 44#include <linux/gpio/driver.h>
 45#include <linux/i2c.h>
 46#include <linux/leds.h>
 47#include <linux/module.h>
 48#include <linux/of.h>
 49#include <linux/property.h>
 50#include <linux/slab.h>
 51#include <linux/string.h>
 52
 53#include <dt-bindings/leds/leds-pca955x.h>
 54
 55/* LED select registers determine the source that drives LED outputs */
 56#define PCA955X_LS_LED_ON	0x0	/* Output LOW */
 57#define PCA955X_LS_LED_OFF	0x1	/* Output HI-Z */
 58#define PCA955X_LS_BLINK0	0x2	/* Blink at PWM0 rate */
 59#define PCA955X_LS_BLINK1	0x3	/* Blink at PWM1 rate */
 60
 61#define PCA955X_GPIO_INPUT	LED_OFF
 62#define PCA955X_GPIO_HIGH	LED_OFF
 63#define PCA955X_GPIO_LOW	LED_FULL
 64
 65#define PCA955X_BLINK_DEFAULT_MS	1000
 66
 67enum pca955x_type {
 68	pca9550,
 69	pca9551,
 70	pca9552,
 71	ibm_pca9552,
 72	pca9553,
 73};
 74
 75struct pca955x_chipdef {
 76	u8			bits;
 77	u8			slv_addr;	/* 7-bit slave address mask */
 78	int			slv_addr_shift;	/* Number of bits to ignore */
 79	int			blink_div;	/* PSC divider */
 80};
 81
 82static const struct pca955x_chipdef pca955x_chipdefs[] = {
 83	[pca9550] = {
 84		.bits		= 2,
 85		.slv_addr	= /* 110000x */ 0x60,
 86		.slv_addr_shift	= 1,
 87		.blink_div	= 44,
 88	},
 89	[pca9551] = {
 90		.bits		= 8,
 91		.slv_addr	= /* 1100xxx */ 0x60,
 92		.slv_addr_shift	= 3,
 93		.blink_div	= 38,
 94	},
 95	[pca9552] = {
 96		.bits		= 16,
 97		.slv_addr	= /* 1100xxx */ 0x60,
 98		.slv_addr_shift	= 3,
 99		.blink_div	= 44,
100	},
101	[ibm_pca9552] = {
102		.bits		= 16,
103		.slv_addr	= /* 0110xxx */ 0x30,
104		.slv_addr_shift	= 3,
105		.blink_div	= 44,
106	},
107	[pca9553] = {
108		.bits		= 4,
109		.slv_addr	= /* 110001x */ 0x62,
110		.slv_addr_shift	= 1,
111		.blink_div	= 44,
112	},
113};
114
115struct pca955x {
116	struct mutex lock;
117	struct pca955x_led *leds;
118	const struct pca955x_chipdef	*chipdef;
119	struct i2c_client	*client;
120	unsigned long active_blink;
121	unsigned long active_pins;
122	unsigned long blink_period;
123#ifdef CONFIG_LEDS_PCA955X_GPIO
124	struct gpio_chip gpio;
125#endif
126};
127
128struct pca955x_led {
129	struct pca955x	*pca955x;
130	struct led_classdev	led_cdev;
131	int			led_num;	/* 0 .. 15 potentially */
132	u32			type;
133	enum led_default_state	default_state;
134	struct fwnode_handle	*fwnode;
135};
136
137#define led_to_pca955x(l)	container_of(l, struct pca955x_led, led_cdev)
138
139struct pca955x_platform_data {
140	struct pca955x_led	*leds;
141	int			num_leds;
142};
143
144/* 8 bits per input register */
145static inline u8 pca955x_num_input_regs(u8 bits)
146{
147	return (bits + 7) / 8;
148}
149
150/* 4 bits per LED selector register */
151static inline u8 pca955x_num_led_regs(u8 bits)
152{
153	return (bits + 3)  / 4;
154}
155
156/*
157 * Return an LED selector register value based on an existing one, with
158 * the appropriate 2-bit state value set for the given LED number (0-3).
159 */
160static inline u8 pca955x_ledsel(u8 oldval, int led_num, int state)
161{
162	return (oldval & (~(0x3 << (led_num << 1)))) |
163		((state & 0x3) << (led_num << 1));
164}
165
166static inline int pca955x_ledstate(u8 ls, int led_num)
167{
168	return (ls >> (led_num << 1)) & 0x3;
169}
170
171/*
172 * Write to frequency prescaler register, used to program the
173 * period of the PWM output.  period = (PSCx + 1) / coeff
174 * Where for pca9551 chips coeff = 38 and for all other chips coeff = 44
175 */
176static int pca955x_write_psc(struct pca955x *pca955x, int n, u8 val)
177{
178	u8 cmd = pca955x_num_input_regs(pca955x->chipdef->bits) + (2 * n);
179	int ret;
180
181	ret = i2c_smbus_write_byte_data(pca955x->client, cmd, val);
182	if (ret < 0)
183		dev_err(&pca955x->client->dev, "%s: reg 0x%x, val 0x%x, err %d\n", __func__, n,
184			val, ret);
185	return ret;
186}
187
188/*
189 * Write to PWM register, which determines the duty cycle of the
190 * output.  LED is OFF when the count is less than the value of this
191 * register, and ON when it is greater.  If PWMx == 0, LED is always OFF.
192 *
193 * Duty cycle is (256 - PWMx) / 256
194 */
195static int pca955x_write_pwm(struct pca955x *pca955x, int n, u8 val)
196{
197	u8 cmd = pca955x_num_input_regs(pca955x->chipdef->bits) + 1 + (2 * n);
198	int ret;
199
200	ret = i2c_smbus_write_byte_data(pca955x->client, cmd, val);
201	if (ret < 0)
202		dev_err(&pca955x->client->dev, "%s: reg 0x%x, val 0x%x, err %d\n", __func__, n,
203			val, ret);
204	return ret;
205}
206
207/*
208 * Write to LED selector register, which determines the source that
209 * drives the LED output.
210 */
211static int pca955x_write_ls(struct pca955x *pca955x, int n, u8 val)
212{
213	u8 cmd = pca955x_num_input_regs(pca955x->chipdef->bits) + 4 + n;
214	int ret;
215
216	ret = i2c_smbus_write_byte_data(pca955x->client, cmd, val);
217	if (ret < 0)
218		dev_err(&pca955x->client->dev, "%s: reg 0x%x, val 0x%x, err %d\n", __func__, n,
219			val, ret);
220	return ret;
221}
222
223/*
224 * Read the LED selector register, which determines the source that
225 * drives the LED output.
226 */
227static int pca955x_read_ls(struct pca955x *pca955x, int n, u8 *val)
228{
229	u8 cmd = pca955x_num_input_regs(pca955x->chipdef->bits) + 4 + n;
230	int ret;
231
232	ret = i2c_smbus_read_byte_data(pca955x->client, cmd);
233	if (ret < 0) {
234		dev_err(&pca955x->client->dev, "%s: reg 0x%x, err %d\n", __func__, n, ret);
235		return ret;
236	}
237	*val = (u8)ret;
238	return 0;
239}
240
241static int pca955x_read_pwm(struct pca955x *pca955x, int n, u8 *val)
242{
243	u8 cmd = pca955x_num_input_regs(pca955x->chipdef->bits) + 1 + (2 * n);
244	int ret;
245
246	ret = i2c_smbus_read_byte_data(pca955x->client, cmd);
247	if (ret < 0) {
248		dev_err(&pca955x->client->dev, "%s: reg 0x%x, err %d\n", __func__, n, ret);
249		return ret;
250	}
251	*val = (u8)ret;
252	return 0;
253}
254
255static int pca955x_read_psc(struct pca955x *pca955x, int n, u8 *val)
256{
257	int ret;
258	u8 cmd;
259
260	cmd = pca955x_num_input_regs(pca955x->chipdef->bits) + (2 * n);
261	ret = i2c_smbus_read_byte_data(pca955x->client, cmd);
262	if (ret < 0) {
263		dev_err(&pca955x->client->dev, "%s: reg 0x%x, err %d\n", __func__, n, ret);
264		return ret;
265	}
266	*val = (u8)ret;
267	return 0;
268}
269
270static enum led_brightness pca955x_led_get(struct led_classdev *led_cdev)
271{
272	struct pca955x_led *pca955x_led = led_to_pca955x(led_cdev);
273	struct pca955x *pca955x = pca955x_led->pca955x;
274	u8 ls, pwm;
275	int ret;
276
277	ret = pca955x_read_ls(pca955x, pca955x_led->led_num / 4, &ls);
278	if (ret)
279		return ret;
280
281	switch (pca955x_ledstate(ls, pca955x_led->led_num % 4)) {
282	case PCA955X_LS_LED_ON:
283	case PCA955X_LS_BLINK0:
284		ret = LED_FULL;
285		break;
286	case PCA955X_LS_LED_OFF:
287		ret = LED_OFF;
288		break;
289	case PCA955X_LS_BLINK1:
290		ret = pca955x_read_pwm(pca955x, 1, &pwm);
291		if (ret)
292			return ret;
293		ret = 255 - pwm;
294		break;
295	}
296
297	return ret;
298}
299
300static int pca955x_led_set(struct led_classdev *led_cdev,
301			    enum led_brightness value)
302{
303	struct pca955x_led *pca955x_led = led_to_pca955x(led_cdev);
304	struct pca955x *pca955x = pca955x_led->pca955x;
305	int reg = pca955x_led->led_num / 4;
306	int bit = pca955x_led->led_num % 4;
307	u8 ls;
308	int ret;
309
310	mutex_lock(&pca955x->lock);
311
312	ret = pca955x_read_ls(pca955x, reg, &ls);
313	if (ret)
314		goto out;
315
316	if (test_bit(pca955x_led->led_num, &pca955x->active_blink)) {
317		if (value == LED_OFF) {
318			clear_bit(pca955x_led->led_num, &pca955x->active_blink);
319			ls = pca955x_ledsel(ls, bit, PCA955X_LS_LED_OFF);
320		} else {
321			/* No variable brightness for blinking LEDs */
322			goto out;
323		}
324	} else {
325		switch (value) {
326		case LED_FULL:
327			ls = pca955x_ledsel(ls, bit, PCA955X_LS_LED_ON);
328			break;
329		case LED_OFF:
330			ls = pca955x_ledsel(ls, bit, PCA955X_LS_LED_OFF);
331			break;
332		default:
333			/*
334			 * Use PWM1 for all other values. This has the unwanted
335			 * side effect of making all LEDs on the chip share the
336			 * same brightness level if set to a value other than
337			 * OFF or FULL. But, this is probably better than just
338			 * turning off for all other values.
339			 */
340			ret = pca955x_write_pwm(pca955x, 1, 255 - value);
341			if (ret)
342				goto out;
343			ls = pca955x_ledsel(ls, bit, PCA955X_LS_BLINK1);
344			break;
345		}
346	}
347
348	ret = pca955x_write_ls(pca955x, reg, ls);
349
350out:
351	mutex_unlock(&pca955x->lock);
352
353	return ret;
354}
355
356static u8 pca955x_period_to_psc(struct pca955x *pca955x, unsigned long period)
357{
358	/* psc register value = (blink period * coeff) - 1 */
359	period *= pca955x->chipdef->blink_div;
360	period /= MSEC_PER_SEC;
361	period -= 1;
362
363	return period;
364}
365
366static unsigned long pca955x_psc_to_period(struct pca955x *pca955x, u8 psc)
367{
368	unsigned long period = psc;
369
370	/* blink period = (psc register value + 1) / coeff */
371	period += 1;
372	period *= MSEC_PER_SEC;
373	period /= pca955x->chipdef->blink_div;
374
375	return period;
376}
377
378static int pca955x_led_blink(struct led_classdev *led_cdev,
379			     unsigned long *delay_on, unsigned long *delay_off)
380{
381	struct pca955x_led *pca955x_led = led_to_pca955x(led_cdev);
382	struct pca955x *pca955x = pca955x_led->pca955x;
383	unsigned long period = *delay_on + *delay_off;
384	int ret = 0;
385
386	mutex_lock(&pca955x->lock);
387
388	if (period) {
389		if (*delay_on != *delay_off) {
390			ret = -EINVAL;
391			goto out;
392		}
393
394		if (period < pca955x_psc_to_period(pca955x, 0) ||
395		    period > pca955x_psc_to_period(pca955x, 0xff)) {
396			ret = -EINVAL;
397			goto out;
398		}
399	} else {
400		period = pca955x->active_blink ? pca955x->blink_period :
401			PCA955X_BLINK_DEFAULT_MS;
402	}
403
404	if (!pca955x->active_blink ||
405	    pca955x->active_blink == BIT(pca955x_led->led_num) ||
406	    pca955x->blink_period == period) {
407		u8 psc = pca955x_period_to_psc(pca955x, period);
408
409		if (!test_and_set_bit(pca955x_led->led_num,
410				      &pca955x->active_blink)) {
411			u8 ls;
412			int reg = pca955x_led->led_num / 4;
413			int bit = pca955x_led->led_num % 4;
414
415			ret = pca955x_read_ls(pca955x, reg, &ls);
416			if (ret)
417				goto out;
418
419			ls = pca955x_ledsel(ls, bit, PCA955X_LS_BLINK0);
420			ret = pca955x_write_ls(pca955x, reg, ls);
421			if (ret)
422				goto out;
423
424			/*
425			 * Force 50% duty cycle to maintain the specified
426			 * blink rate.
427			 */
428			ret = pca955x_write_pwm(pca955x, 0, 128);
429			if (ret)
430				goto out;
431		}
432
433		if (pca955x->blink_period != period) {
434			pca955x->blink_period = period;
435			ret = pca955x_write_psc(pca955x, 0, psc);
436			if (ret)
437				goto out;
438		}
439
440		period = pca955x_psc_to_period(pca955x, psc);
441		period /= 2;
442		*delay_on = period;
443		*delay_off = period;
444	} else {
445		ret = -EBUSY;
446	}
447
448out:
449	mutex_unlock(&pca955x->lock);
450
451	return ret;
452}
453
454#ifdef CONFIG_LEDS_PCA955X_GPIO
455/*
456 * Read the INPUT register, which contains the state of LEDs.
457 */
458static int pca955x_read_input(struct i2c_client *client, int n, u8 *val)
459{
460	int ret = i2c_smbus_read_byte_data(client, n);
461
462	if (ret < 0) {
463		dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
464			__func__, n, ret);
465		return ret;
466	}
467	*val = (u8)ret;
468	return 0;
469
470}
471
472static int pca955x_gpio_request_pin(struct gpio_chip *gc, unsigned int offset)
473{
474	struct pca955x *pca955x = gpiochip_get_data(gc);
475
476	return test_and_set_bit(offset, &pca955x->active_pins) ? -EBUSY : 0;
477}
478
479static void pca955x_gpio_free_pin(struct gpio_chip *gc, unsigned int offset)
480{
481	struct pca955x *pca955x = gpiochip_get_data(gc);
482
483	clear_bit(offset, &pca955x->active_pins);
484}
485
486static int pca955x_set_value(struct gpio_chip *gc, unsigned int offset,
487			     int val)
488{
489	struct pca955x *pca955x = gpiochip_get_data(gc);
490	struct pca955x_led *led = &pca955x->leds[offset];
491
492	if (val)
493		return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_HIGH);
494
495	return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_LOW);
496}
497
498static int pca955x_gpio_set_value(struct gpio_chip *gc, unsigned int offset,
499				  int val)
500{
501	return pca955x_set_value(gc, offset, val);
502}
503
504static int pca955x_gpio_get_value(struct gpio_chip *gc, unsigned int offset)
505{
506	struct pca955x *pca955x = gpiochip_get_data(gc);
507	struct pca955x_led *led = &pca955x->leds[offset];
508	u8 reg = 0;
509
510	/* There is nothing we can do about errors */
511	pca955x_read_input(pca955x->client, led->led_num / 8, &reg);
512
513	return !!(reg & (1 << (led->led_num % 8)));
514}
515
516static int pca955x_gpio_direction_input(struct gpio_chip *gc,
517					unsigned int offset)
518{
519	struct pca955x *pca955x = gpiochip_get_data(gc);
520	struct pca955x_led *led = &pca955x->leds[offset];
521
522	/* To use as input ensure pin is not driven. */
523	return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_INPUT);
524}
525
526static int pca955x_gpio_direction_output(struct gpio_chip *gc,
527					 unsigned int offset, int val)
528{
529	return pca955x_set_value(gc, offset, val);
530}
531#endif /* CONFIG_LEDS_PCA955X_GPIO */
532
533static struct pca955x_platform_data *
534pca955x_get_pdata(struct i2c_client *client, const struct pca955x_chipdef *chip)
535{
536	struct pca955x_platform_data *pdata;
537	struct pca955x_led *led;
538	struct fwnode_handle *child;
539	int count;
540
541	count = device_get_child_node_count(&client->dev);
542	if (count > chip->bits)
543		return ERR_PTR(-ENODEV);
544
545	pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
546	if (!pdata)
547		return ERR_PTR(-ENOMEM);
548
549	pdata->leds = devm_kcalloc(&client->dev,
550				   chip->bits, sizeof(struct pca955x_led),
551				   GFP_KERNEL);
552	if (!pdata->leds)
553		return ERR_PTR(-ENOMEM);
554
555	device_for_each_child_node(&client->dev, child) {
556		u32 reg;
557		int res;
558
559		res = fwnode_property_read_u32(child, "reg", &reg);
560		if ((res != 0) || (reg >= chip->bits))
561			continue;
562
563		led = &pdata->leds[reg];
564		led->type = PCA955X_TYPE_LED;
565		led->fwnode = child;
566		led->default_state = led_init_default_state_get(child);
567
568		fwnode_property_read_u32(child, "type", &led->type);
569	}
570
571	pdata->num_leds = chip->bits;
572
573	return pdata;
574}
575
576static int pca955x_probe(struct i2c_client *client)
577{
578	struct pca955x *pca955x;
579	struct pca955x_led *pca955x_led;
580	const struct pca955x_chipdef *chip;
581	struct led_classdev *led;
582	struct led_init_data init_data;
583	struct i2c_adapter *adapter;
584	u8 i, nls, psc0;
585	u8 ls1[4];
586	u8 ls2[4];
587	struct pca955x_platform_data *pdata;
588	bool keep_psc0 = false;
589	bool set_default_label = false;
590	char default_label[4];
591	int bit, err, reg;
592
593	chip = i2c_get_match_data(client);
594	if (!chip)
595		return dev_err_probe(&client->dev, -ENODEV, "unknown chip\n");
596
597	adapter = client->adapter;
598	pdata = dev_get_platdata(&client->dev);
599	if (!pdata) {
600		pdata =	pca955x_get_pdata(client, chip);
601		if (IS_ERR(pdata))
602			return PTR_ERR(pdata);
603	}
604
605	/* Make sure the slave address / chip type combo given is possible */
606	if ((client->addr & ~((1 << chip->slv_addr_shift) - 1)) !=
607	    chip->slv_addr) {
608		dev_err(&client->dev, "invalid slave address %02x\n",
609			client->addr);
610		return -ENODEV;
611	}
612
613	dev_info(&client->dev, "Using %s %u-bit LED driver at slave address 0x%02x\n",
614		 client->name, chip->bits, client->addr);
615
616	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
617		return -EIO;
618
619	if (pdata->num_leds != chip->bits) {
620		dev_err(&client->dev,
621			"board info claims %d LEDs on a %u-bit chip\n",
622			pdata->num_leds, chip->bits);
623		return -ENODEV;
624	}
625
626	pca955x = devm_kzalloc(&client->dev, sizeof(*pca955x), GFP_KERNEL);
627	if (!pca955x)
628		return -ENOMEM;
629
630	pca955x->leds = devm_kcalloc(&client->dev, chip->bits,
631				     sizeof(*pca955x_led), GFP_KERNEL);
632	if (!pca955x->leds)
633		return -ENOMEM;
634
635	i2c_set_clientdata(client, pca955x);
636
637	mutex_init(&pca955x->lock);
638	pca955x->client = client;
639	pca955x->chipdef = chip;
640	pca955x->blink_period = PCA955X_BLINK_DEFAULT_MS;
641
642	init_data.devname_mandatory = false;
643	init_data.devicename = "pca955x";
644
645	nls = pca955x_num_led_regs(chip->bits);
646	/* Use auto-increment feature to read all the LED selectors at once. */
647	err = i2c_smbus_read_i2c_block_data(client,
648					    0x10 | (pca955x_num_input_regs(chip->bits) + 4), nls,
649					    ls1);
650	if (err < 0)
651		return err;
652
653	for (i = 0; i < nls; i++)
654		ls2[i] = ls1[i];
655
656	for (i = 0; i < chip->bits; i++) {
657		pca955x_led = &pca955x->leds[i];
658		pca955x_led->led_num = i;
659		pca955x_led->pca955x = pca955x;
660		pca955x_led->type = pdata->leds[i].type;
661
662		switch (pca955x_led->type) {
663		case PCA955X_TYPE_NONE:
664		case PCA955X_TYPE_GPIO:
665			break;
666		case PCA955X_TYPE_LED:
667			bit = i % 4;
668			reg = i / 4;
669			led = &pca955x_led->led_cdev;
670			led->brightness_set_blocking = pca955x_led_set;
671			led->brightness_get = pca955x_led_get;
672			led->blink_set = pca955x_led_blink;
673
674			if (pdata->leds[i].default_state == LEDS_DEFSTATE_OFF)
675				ls2[reg] = pca955x_ledsel(ls2[reg], bit, PCA955X_LS_LED_OFF);
676			else if (pdata->leds[i].default_state == LEDS_DEFSTATE_ON)
677				ls2[reg] = pca955x_ledsel(ls2[reg], bit, PCA955X_LS_LED_ON);
678			else if (pca955x_ledstate(ls2[reg], bit) == PCA955X_LS_BLINK0) {
679				keep_psc0 = true;
680				set_bit(i, &pca955x->active_blink);
681			}
682
683			init_data.fwnode = pdata->leds[i].fwnode;
684
685			if (is_of_node(init_data.fwnode)) {
686				if (to_of_node(init_data.fwnode)->name[0] ==
687				    '\0')
688					set_default_label = true;
689				else
690					set_default_label = false;
691			} else {
692				set_default_label = true;
693			}
694
695			if (set_default_label) {
696				snprintf(default_label, sizeof(default_label), "%hhu", i);
697				init_data.default_label = default_label;
698			} else {
699				init_data.default_label = NULL;
700			}
701
702			err = devm_led_classdev_register_ext(&client->dev, led,
703							     &init_data);
704			if (err)
705				return err;
706
707			set_bit(i, &pca955x->active_pins);
708		}
709	}
710
711	for (i = 0; i < nls; i++) {
712		if (ls1[i] != ls2[i]) {
713			err = pca955x_write_ls(pca955x, i, ls2[i]);
714			if (err)
715				return err;
716		}
717	}
718
719	if (keep_psc0) {
720		err = pca955x_read_psc(pca955x, 0, &psc0);
721	} else {
722		psc0 = pca955x_period_to_psc(pca955x, pca955x->blink_period);
723		err = pca955x_write_psc(pca955x, 0, psc0);
724	}
725
726	if (err)
727		return err;
728
729	pca955x->blink_period = pca955x_psc_to_period(pca955x, psc0);
730
731	/* Set PWM1 to fast frequency so we do not see flashing */
732	err = pca955x_write_psc(pca955x, 1, 0);
733	if (err)
734		return err;
735
736#ifdef CONFIG_LEDS_PCA955X_GPIO
737	pca955x->gpio.label = "gpio-pca955x";
738	pca955x->gpio.direction_input = pca955x_gpio_direction_input;
739	pca955x->gpio.direction_output = pca955x_gpio_direction_output;
740	pca955x->gpio.set = pca955x_gpio_set_value;
741	pca955x->gpio.get = pca955x_gpio_get_value;
742	pca955x->gpio.request = pca955x_gpio_request_pin;
743	pca955x->gpio.free = pca955x_gpio_free_pin;
744	pca955x->gpio.can_sleep = 1;
745	pca955x->gpio.base = -1;
746	pca955x->gpio.ngpio = chip->bits;
747	pca955x->gpio.parent = &client->dev;
748	pca955x->gpio.owner = THIS_MODULE;
749
750	err = devm_gpiochip_add_data(&client->dev, &pca955x->gpio,
751				     pca955x);
752	if (err) {
753		/* Use data->gpio.dev as a flag for freeing gpiochip */
754		pca955x->gpio.parent = NULL;
755		dev_warn(&client->dev, "could not add gpiochip\n");
756		return err;
757	}
758	dev_info(&client->dev, "gpios %i...%i\n",
759		 pca955x->gpio.base, pca955x->gpio.base +
760		 pca955x->gpio.ngpio - 1);
761#endif
762
763	return 0;
764}
765
766static const struct i2c_device_id pca955x_id[] = {
767	{ "pca9550", (kernel_ulong_t)&pca955x_chipdefs[pca9550] },
768	{ "pca9551", (kernel_ulong_t)&pca955x_chipdefs[pca9551] },
769	{ "pca9552", (kernel_ulong_t)&pca955x_chipdefs[pca9552] },
770	{ "ibm-pca9552", (kernel_ulong_t)&pca955x_chipdefs[ibm_pca9552] },
771	{ "pca9553", (kernel_ulong_t)&pca955x_chipdefs[pca9553] },
772	{}
773};
774MODULE_DEVICE_TABLE(i2c, pca955x_id);
775
776static const struct of_device_id of_pca955x_match[] = {
777	{ .compatible = "nxp,pca9550", .data = &pca955x_chipdefs[pca9550] },
778	{ .compatible = "nxp,pca9551", .data = &pca955x_chipdefs[pca9551] },
779	{ .compatible = "nxp,pca9552", .data = &pca955x_chipdefs[pca9552] },
780	{ .compatible = "ibm,pca9552", .data = &pca955x_chipdefs[ibm_pca9552] },
781	{ .compatible = "nxp,pca9553", .data = &pca955x_chipdefs[pca9553] },
782	{}
783};
784MODULE_DEVICE_TABLE(of, of_pca955x_match);
785
786static struct i2c_driver pca955x_driver = {
787	.driver = {
788		.name	= "leds-pca955x",
789		.of_match_table = of_pca955x_match,
790	},
791	.probe = pca955x_probe,
792	.id_table = pca955x_id,
793};
794
795module_i2c_driver(pca955x_driver);
796
797MODULE_AUTHOR("Nate Case <ncase@xes-inc.com>");
798MODULE_DESCRIPTION("PCA955x LED driver");
799MODULE_LICENSE("GPL v2");