forked from mirrors/linux
		
	pwm: atmel: add Timer Counter Block PWM driver
This patch adds a PWM driver based on Atmel Timer Counter Block. The Timer Counter Block is used in Waveform generator mode. A Timer Counter Block provides up to 6 PWM devices grouped by 2: * group 0 = PWM 0 and 1 * group 1 = PWM 2 and 3 * group 2 = PMW 4 and 5 PWM devices in a given group must be configured with the same period value. If a PWM device in a group tries to change the period value and the other device is already configured with a different value an error will be returned. This driver requires device tree support. The Timer Counter Block number used to create a PWM chip is given by the tc-block field in an "atmel,tcb-pwm" compatible node. This patch was tested on kizbox board (at91sam9g20 SoC) with pwm-leds. Signed-off-by: Boris BREZILLON <linux-arm@overkiz.com> Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
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								Documentation/devicetree/bindings/pwm/atmel-tcb-pwm.txt
									
									
									
									
									
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								Documentation/devicetree/bindings/pwm/atmel-tcb-pwm.txt
									
									
									
									
									
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							|  | @ -0,0 +1,18 @@ | |||
| Atmel TCB PWM controller | ||||
| 
 | ||||
| Required properties: | ||||
| - compatible: should be "atmel,tcb-pwm" | ||||
| - #pwm-cells: Should be 3.  The first cell specifies the per-chip index | ||||
|   of the PWM to use, the second cell is the period in nanoseconds and | ||||
|   bit 0 in the third cell is used to encode the polarity of PWM output. | ||||
|   Set bit 0 of the third cell in PWM specifier to 1 for inverse polarity & | ||||
|   set to 0 for normal polarity. | ||||
| - tc-block: The Timer Counter block to use as a PWM chip. | ||||
| 
 | ||||
| Example: | ||||
| 
 | ||||
| pwm { | ||||
| 	compatible = "atmel,tcb-pwm"; | ||||
| 	#pwm-cells = <3>; | ||||
| 	tc-block = <1>; | ||||
| }; | ||||
|  | @ -37,6 +37,18 @@ config PWM_AB8500 | |||
| 	  To compile this driver as a module, choose M here: the module | ||||
| 	  will be called pwm-ab8500. | ||||
| 
 | ||||
| config PWM_ATMEL_TCB | ||||
| 	tristate "TC Block PWM" | ||||
| 	depends on ATMEL_TCLIB && OF | ||||
| 	help | ||||
| 	  Generic PWM framework driver for Atmel Timer Counter Block. | ||||
| 
 | ||||
| 	  A Timer Counter Block provides 6 PWM devices grouped by 2. | ||||
| 	  Devices in a given group must have the same period. | ||||
| 
 | ||||
| 	  To compile this driver as a module, choose M here: the module | ||||
| 	  will be called pwm-atmel-tcb. | ||||
| 
 | ||||
| config PWM_BFIN | ||||
| 	tristate "Blackfin PWM support" | ||||
| 	depends on BFIN_GPTIMERS | ||||
|  |  | |||
|  | @ -1,5 +1,6 @@ | |||
| obj-$(CONFIG_PWM)		+= core.o | ||||
| obj-$(CONFIG_PWM_AB8500)	+= pwm-ab8500.o | ||||
| obj-$(CONFIG_PWM_ATMEL_TCB)	+= pwm-atmel-tcb.o | ||||
| obj-$(CONFIG_PWM_BFIN)		+= pwm-bfin.o | ||||
| obj-$(CONFIG_PWM_IMX)		+= pwm-imx.o | ||||
| obj-$(CONFIG_PWM_JZ4740)	+= pwm-jz4740.o | ||||
|  |  | |||
							
								
								
									
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								drivers/pwm/pwm-atmel-tcb.c
									
									
									
									
									
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								drivers/pwm/pwm-atmel-tcb.c
									
									
									
									
									
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							|  | @ -0,0 +1,445 @@ | |||
| /*
 | ||||
|  * Copyright (C) Overkiz SAS 2012 | ||||
|  * | ||||
|  * Author: Boris BREZILLON <b.brezillon@overkiz.com> | ||||
|  * License terms: GNU General Public License (GPL) version 2 | ||||
|  */ | ||||
| 
 | ||||
| #include <linux/module.h> | ||||
| #include <linux/init.h> | ||||
| #include <linux/clocksource.h> | ||||
| #include <linux/clockchips.h> | ||||
| #include <linux/interrupt.h> | ||||
| #include <linux/irq.h> | ||||
| 
 | ||||
| #include <linux/clk.h> | ||||
| #include <linux/err.h> | ||||
| #include <linux/ioport.h> | ||||
| #include <linux/io.h> | ||||
| #include <linux/platform_device.h> | ||||
| #include <linux/atmel_tc.h> | ||||
| #include <linux/pwm.h> | ||||
| #include <linux/of_device.h> | ||||
| #include <linux/slab.h> | ||||
| 
 | ||||
| #define NPWM	6 | ||||
| 
 | ||||
| #define ATMEL_TC_ACMR_MASK	(ATMEL_TC_ACPA | ATMEL_TC_ACPC |	\ | ||||
| 				 ATMEL_TC_AEEVT | ATMEL_TC_ASWTRG) | ||||
| 
 | ||||
| #define ATMEL_TC_BCMR_MASK	(ATMEL_TC_BCPB | ATMEL_TC_BCPC |	\ | ||||
| 				 ATMEL_TC_BEEVT | ATMEL_TC_BSWTRG) | ||||
| 
 | ||||
| struct atmel_tcb_pwm_device { | ||||
| 	enum pwm_polarity polarity;	/* PWM polarity */ | ||||
| 	unsigned div;			/* PWM clock divider */ | ||||
| 	unsigned duty;			/* PWM duty expressed in clk cycles */ | ||||
| 	unsigned period;		/* PWM period expressed in clk cycles */ | ||||
| }; | ||||
| 
 | ||||
| struct atmel_tcb_pwm_chip { | ||||
| 	struct pwm_chip chip; | ||||
| 	spinlock_t lock; | ||||
| 	struct atmel_tc *tc; | ||||
| 	struct atmel_tcb_pwm_device *pwms[NPWM]; | ||||
| }; | ||||
| 
 | ||||
| static inline struct atmel_tcb_pwm_chip *to_tcb_chip(struct pwm_chip *chip) | ||||
| { | ||||
| 	return container_of(chip, struct atmel_tcb_pwm_chip, chip); | ||||
| } | ||||
| 
 | ||||
| static int atmel_tcb_pwm_set_polarity(struct pwm_chip *chip, | ||||
| 				      struct pwm_device *pwm, | ||||
| 				      enum pwm_polarity polarity) | ||||
| { | ||||
| 	struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm); | ||||
| 
 | ||||
| 	tcbpwm->polarity = polarity; | ||||
| 
 | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| static int atmel_tcb_pwm_request(struct pwm_chip *chip, | ||||
| 				 struct pwm_device *pwm) | ||||
| { | ||||
| 	struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip); | ||||
| 	struct atmel_tcb_pwm_device *tcbpwm; | ||||
| 	struct atmel_tc *tc = tcbpwmc->tc; | ||||
| 	void __iomem *regs = tc->regs; | ||||
| 	unsigned group = pwm->hwpwm / 2; | ||||
| 	unsigned index = pwm->hwpwm % 2; | ||||
| 	unsigned cmr; | ||||
| 	int ret; | ||||
| 
 | ||||
| 	tcbpwm = devm_kzalloc(chip->dev, sizeof(*tcbpwm), GFP_KERNEL); | ||||
| 	if (!tcbpwm) | ||||
| 		return -ENOMEM; | ||||
| 
 | ||||
| 	ret = clk_enable(tc->clk[group]); | ||||
| 	if (ret) { | ||||
| 		devm_kfree(chip->dev, tcbpwm); | ||||
| 		return ret; | ||||
| 	} | ||||
| 
 | ||||
| 	pwm_set_chip_data(pwm, tcbpwm); | ||||
| 	tcbpwm->polarity = PWM_POLARITY_NORMAL; | ||||
| 	tcbpwm->duty = 0; | ||||
| 	tcbpwm->period = 0; | ||||
| 	tcbpwm->div = 0; | ||||
| 
 | ||||
| 	spin_lock(&tcbpwmc->lock); | ||||
| 	cmr = __raw_readl(regs + ATMEL_TC_REG(group, CMR)); | ||||
| 	/*
 | ||||
| 	 * Get init config from Timer Counter registers if | ||||
| 	 * Timer Counter is already configured as a PWM generator. | ||||
| 	 */ | ||||
| 	if (cmr & ATMEL_TC_WAVE) { | ||||
| 		if (index == 0) | ||||
| 			tcbpwm->duty = | ||||
| 				__raw_readl(regs + ATMEL_TC_REG(group, RA)); | ||||
| 		else | ||||
| 			tcbpwm->duty = | ||||
| 				__raw_readl(regs + ATMEL_TC_REG(group, RB)); | ||||
| 
 | ||||
| 		tcbpwm->div = cmr & ATMEL_TC_TCCLKS; | ||||
| 		tcbpwm->period = __raw_readl(regs + ATMEL_TC_REG(group, RC)); | ||||
| 		cmr &= (ATMEL_TC_TCCLKS | ATMEL_TC_ACMR_MASK | | ||||
| 			ATMEL_TC_BCMR_MASK); | ||||
| 	} else | ||||
| 		cmr = 0; | ||||
| 
 | ||||
| 	cmr |= ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO | ATMEL_TC_EEVT_XC0; | ||||
| 	__raw_writel(cmr, regs + ATMEL_TC_REG(group, CMR)); | ||||
| 	spin_unlock(&tcbpwmc->lock); | ||||
| 
 | ||||
| 	tcbpwmc->pwms[pwm->hwpwm] = tcbpwm; | ||||
| 
 | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| static void atmel_tcb_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) | ||||
| { | ||||
| 	struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip); | ||||
| 	struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm); | ||||
| 	struct atmel_tc *tc = tcbpwmc->tc; | ||||
| 
 | ||||
| 	clk_disable(tc->clk[pwm->hwpwm / 2]); | ||||
| 	tcbpwmc->pwms[pwm->hwpwm] = NULL; | ||||
| 	devm_kfree(chip->dev, tcbpwm); | ||||
| } | ||||
| 
 | ||||
| static void atmel_tcb_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) | ||||
| { | ||||
| 	struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip); | ||||
| 	struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm); | ||||
| 	struct atmel_tc *tc = tcbpwmc->tc; | ||||
| 	void __iomem *regs = tc->regs; | ||||
| 	unsigned group = pwm->hwpwm / 2; | ||||
| 	unsigned index = pwm->hwpwm % 2; | ||||
| 	unsigned cmr; | ||||
| 	enum pwm_polarity polarity = tcbpwm->polarity; | ||||
| 
 | ||||
| 	/*
 | ||||
| 	 * If duty is 0 the timer will be stopped and we have to | ||||
| 	 * configure the output correctly on software trigger: | ||||
| 	 *  - set output to high if PWM_POLARITY_INVERSED | ||||
| 	 *  - set output to low if PWM_POLARITY_NORMAL | ||||
| 	 * | ||||
| 	 * This is why we're reverting polarity in this case. | ||||
| 	 */ | ||||
| 	if (tcbpwm->duty == 0) | ||||
| 		polarity = !polarity; | ||||
| 
 | ||||
| 	spin_lock(&tcbpwmc->lock); | ||||
| 	cmr = __raw_readl(regs + ATMEL_TC_REG(group, CMR)); | ||||
| 
 | ||||
| 	/* flush old setting and set the new one */ | ||||
| 	if (index == 0) { | ||||
| 		cmr &= ~ATMEL_TC_ACMR_MASK; | ||||
| 		if (polarity == PWM_POLARITY_INVERSED) | ||||
| 			cmr |= ATMEL_TC_ASWTRG_CLEAR; | ||||
| 		else | ||||
| 			cmr |= ATMEL_TC_ASWTRG_SET; | ||||
| 	} else { | ||||
| 		cmr &= ~ATMEL_TC_BCMR_MASK; | ||||
| 		if (polarity == PWM_POLARITY_INVERSED) | ||||
| 			cmr |= ATMEL_TC_BSWTRG_CLEAR; | ||||
| 		else | ||||
| 			cmr |= ATMEL_TC_BSWTRG_SET; | ||||
| 	} | ||||
| 
 | ||||
| 	__raw_writel(cmr, regs + ATMEL_TC_REG(group, CMR)); | ||||
| 
 | ||||
| 	/*
 | ||||
| 	 * Use software trigger to apply the new setting. | ||||
| 	 * If both PWM devices in this group are disabled we stop the clock. | ||||
| 	 */ | ||||
| 	if (!(cmr & (ATMEL_TC_ACPC | ATMEL_TC_BCPC))) | ||||
| 		__raw_writel(ATMEL_TC_SWTRG | ATMEL_TC_CLKDIS, | ||||
| 			     regs + ATMEL_TC_REG(group, CCR)); | ||||
| 	else | ||||
| 		__raw_writel(ATMEL_TC_SWTRG, regs + | ||||
| 			     ATMEL_TC_REG(group, CCR)); | ||||
| 
 | ||||
| 	spin_unlock(&tcbpwmc->lock); | ||||
| } | ||||
| 
 | ||||
| static int atmel_tcb_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) | ||||
| { | ||||
| 	struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip); | ||||
| 	struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm); | ||||
| 	struct atmel_tc *tc = tcbpwmc->tc; | ||||
| 	void __iomem *regs = tc->regs; | ||||
| 	unsigned group = pwm->hwpwm / 2; | ||||
| 	unsigned index = pwm->hwpwm % 2; | ||||
| 	u32 cmr; | ||||
| 	enum pwm_polarity polarity = tcbpwm->polarity; | ||||
| 
 | ||||
| 	/*
 | ||||
| 	 * If duty is 0 the timer will be stopped and we have to | ||||
| 	 * configure the output correctly on software trigger: | ||||
| 	 *  - set output to high if PWM_POLARITY_INVERSED | ||||
| 	 *  - set output to low if PWM_POLARITY_NORMAL | ||||
| 	 * | ||||
| 	 * This is why we're reverting polarity in this case. | ||||
| 	 */ | ||||
| 	if (tcbpwm->duty == 0) | ||||
| 		polarity = !polarity; | ||||
| 
 | ||||
| 	spin_lock(&tcbpwmc->lock); | ||||
| 	cmr = __raw_readl(regs + ATMEL_TC_REG(group, CMR)); | ||||
| 
 | ||||
| 	/* flush old setting and set the new one */ | ||||
| 	cmr &= ~ATMEL_TC_TCCLKS; | ||||
| 
 | ||||
| 	if (index == 0) { | ||||
| 		cmr &= ~ATMEL_TC_ACMR_MASK; | ||||
| 
 | ||||
| 		/* Set CMR flags according to given polarity */ | ||||
| 		if (polarity == PWM_POLARITY_INVERSED) | ||||
| 			cmr |= ATMEL_TC_ASWTRG_CLEAR; | ||||
| 		else | ||||
| 			cmr |= ATMEL_TC_ASWTRG_SET; | ||||
| 	} else { | ||||
| 		cmr &= ~ATMEL_TC_BCMR_MASK; | ||||
| 		if (polarity == PWM_POLARITY_INVERSED) | ||||
| 			cmr |= ATMEL_TC_BSWTRG_CLEAR; | ||||
| 		else | ||||
| 			cmr |= ATMEL_TC_BSWTRG_SET; | ||||
| 	} | ||||
| 
 | ||||
| 	/*
 | ||||
| 	 * If duty is 0 or equal to period there's no need to register | ||||
| 	 * a specific action on RA/RB and RC compare. | ||||
| 	 * The output will be configured on software trigger and keep | ||||
| 	 * this config till next config call. | ||||
| 	 */ | ||||
| 	if (tcbpwm->duty != tcbpwm->period && tcbpwm->duty > 0) { | ||||
| 		if (index == 0) { | ||||
| 			if (polarity == PWM_POLARITY_INVERSED) | ||||
| 				cmr |= ATMEL_TC_ACPA_SET | ATMEL_TC_ACPC_CLEAR; | ||||
| 			else | ||||
| 				cmr |= ATMEL_TC_ACPA_CLEAR | ATMEL_TC_ACPC_SET; | ||||
| 		} else { | ||||
| 			if (polarity == PWM_POLARITY_INVERSED) | ||||
| 				cmr |= ATMEL_TC_BCPB_SET | ATMEL_TC_BCPC_CLEAR; | ||||
| 			else | ||||
| 				cmr |= ATMEL_TC_BCPB_CLEAR | ATMEL_TC_BCPC_SET; | ||||
| 		} | ||||
| 	} | ||||
| 
 | ||||
| 	__raw_writel(cmr, regs + ATMEL_TC_REG(group, CMR)); | ||||
| 
 | ||||
| 	if (index == 0) | ||||
| 		__raw_writel(tcbpwm->duty, regs + ATMEL_TC_REG(group, RA)); | ||||
| 	else | ||||
| 		__raw_writel(tcbpwm->duty, regs + ATMEL_TC_REG(group, RB)); | ||||
| 
 | ||||
| 	__raw_writel(tcbpwm->period, regs + ATMEL_TC_REG(group, RC)); | ||||
| 
 | ||||
| 	/* Use software trigger to apply the new setting */ | ||||
| 	__raw_writel(ATMEL_TC_CLKEN | ATMEL_TC_SWTRG, | ||||
| 		     regs + ATMEL_TC_REG(group, CCR)); | ||||
| 	spin_unlock(&tcbpwmc->lock); | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| static int atmel_tcb_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, | ||||
| 				int duty_ns, int period_ns) | ||||
| { | ||||
| 	struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip); | ||||
| 	struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm); | ||||
| 	unsigned group = pwm->hwpwm / 2; | ||||
| 	unsigned index = pwm->hwpwm % 2; | ||||
| 	struct atmel_tcb_pwm_device *atcbpwm = NULL; | ||||
| 	struct atmel_tc *tc = tcbpwmc->tc; | ||||
| 	int i; | ||||
| 	int slowclk = 0; | ||||
| 	unsigned period; | ||||
| 	unsigned duty; | ||||
| 	unsigned rate = clk_get_rate(tc->clk[group]); | ||||
| 	unsigned long long min; | ||||
| 	unsigned long long max; | ||||
| 
 | ||||
| 	/*
 | ||||
| 	 * Find best clk divisor: | ||||
| 	 * the smallest divisor which can fulfill the period_ns requirements. | ||||
| 	 */ | ||||
| 	for (i = 0; i < 5; ++i) { | ||||
| 		if (atmel_tc_divisors[i] == 0) { | ||||
| 			slowclk = i; | ||||
| 			continue; | ||||
| 		} | ||||
| 		min = div_u64((u64)NSEC_PER_SEC * atmel_tc_divisors[i], rate); | ||||
| 		max = min << tc->tcb_config->counter_width; | ||||
| 		if (max >= period_ns) | ||||
| 			break; | ||||
| 	} | ||||
| 
 | ||||
| 	/*
 | ||||
| 	 * If none of the divisor are small enough to represent period_ns | ||||
| 	 * take slow clock (32KHz). | ||||
| 	 */ | ||||
| 	if (i == 5) { | ||||
| 		i = slowclk; | ||||
| 		rate = 32768; | ||||
| 		min = div_u64(NSEC_PER_SEC, rate); | ||||
| 		max = min << 16; | ||||
| 
 | ||||
| 		/* If period is too big return ERANGE error */ | ||||
| 		if (max < period_ns) | ||||
| 			return -ERANGE; | ||||
| 	} | ||||
| 
 | ||||
| 	duty = div_u64(duty_ns, min); | ||||
| 	period = div_u64(period_ns, min); | ||||
| 
 | ||||
| 	if (index == 0) | ||||
| 		atcbpwm = tcbpwmc->pwms[pwm->hwpwm + 1]; | ||||
| 	else | ||||
| 		atcbpwm = tcbpwmc->pwms[pwm->hwpwm - 1]; | ||||
| 
 | ||||
| 	/*
 | ||||
| 	 * PWM devices provided by TCB driver are grouped by 2: | ||||
| 	 * - group 0: PWM 0 & 1 | ||||
| 	 * - group 1: PWM 2 & 3 | ||||
| 	 * - group 2: PWM 4 & 5 | ||||
| 	 * | ||||
| 	 * PWM devices in a given group must be configured with the | ||||
| 	 * same period_ns. | ||||
| 	 * | ||||
| 	 * We're checking the period value of the second PWM device | ||||
| 	 * in this group before applying the new config. | ||||
| 	 */ | ||||
| 	if ((atcbpwm && atcbpwm->duty > 0 && | ||||
| 			atcbpwm->duty != atcbpwm->period) && | ||||
| 		(atcbpwm->div != i || atcbpwm->period != period)) { | ||||
| 		dev_err(chip->dev, | ||||
| 			"failed to configure period_ns: PWM group already configured with a different value\n"); | ||||
| 		return -EINVAL; | ||||
| 	} | ||||
| 
 | ||||
| 	tcbpwm->period = period; | ||||
| 	tcbpwm->div = i; | ||||
| 	tcbpwm->duty = duty; | ||||
| 
 | ||||
| 	/* If the PWM is enabled, call enable to apply the new conf */ | ||||
| 	if (test_bit(PWMF_ENABLED, &pwm->flags)) | ||||
| 		atmel_tcb_pwm_enable(chip, pwm); | ||||
| 
 | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| static const struct pwm_ops atmel_tcb_pwm_ops = { | ||||
| 	.request = atmel_tcb_pwm_request, | ||||
| 	.free = atmel_tcb_pwm_free, | ||||
| 	.config = atmel_tcb_pwm_config, | ||||
| 	.set_polarity = atmel_tcb_pwm_set_polarity, | ||||
| 	.enable = atmel_tcb_pwm_enable, | ||||
| 	.disable = atmel_tcb_pwm_disable, | ||||
| }; | ||||
| 
 | ||||
| static int atmel_tcb_pwm_probe(struct platform_device *pdev) | ||||
| { | ||||
| 	struct atmel_tcb_pwm_chip *tcbpwm; | ||||
| 	struct device_node *np = pdev->dev.of_node; | ||||
| 	struct atmel_tc *tc; | ||||
| 	int err; | ||||
| 	int tcblock; | ||||
| 
 | ||||
| 	err = of_property_read_u32(np, "tc-block", &tcblock); | ||||
| 	if (err < 0) { | ||||
| 		dev_err(&pdev->dev, | ||||
| 			"failed to get Timer Counter Block number from device tree (error: %d)\n", | ||||
| 			err); | ||||
| 		return err; | ||||
| 	} | ||||
| 
 | ||||
| 	tc = atmel_tc_alloc(tcblock, "tcb-pwm"); | ||||
| 	if (tc == NULL) { | ||||
| 		dev_err(&pdev->dev, "failed to allocate Timer Counter Block\n"); | ||||
| 		return -ENOMEM; | ||||
| 	} | ||||
| 
 | ||||
| 	tcbpwm = devm_kzalloc(&pdev->dev, sizeof(*tcbpwm), GFP_KERNEL); | ||||
| 	if (tcbpwm == NULL) { | ||||
| 		atmel_tc_free(tc); | ||||
| 		dev_err(&pdev->dev, "failed to allocate memory\n"); | ||||
| 		return -ENOMEM; | ||||
| 	} | ||||
| 
 | ||||
| 	tcbpwm->chip.dev = &pdev->dev; | ||||
| 	tcbpwm->chip.ops = &atmel_tcb_pwm_ops; | ||||
| 	tcbpwm->chip.of_xlate = of_pwm_xlate_with_flags; | ||||
| 	tcbpwm->chip.of_pwm_n_cells = 3; | ||||
| 	tcbpwm->chip.base = -1; | ||||
| 	tcbpwm->chip.npwm = NPWM; | ||||
| 	tcbpwm->tc = tc; | ||||
| 
 | ||||
| 	spin_lock_init(&tcbpwm->lock); | ||||
| 
 | ||||
| 	err = pwmchip_add(&tcbpwm->chip); | ||||
| 	if (err < 0) { | ||||
| 		atmel_tc_free(tc); | ||||
| 		return err; | ||||
| 	} | ||||
| 
 | ||||
| 	platform_set_drvdata(pdev, tcbpwm); | ||||
| 
 | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| static int atmel_tcb_pwm_remove(struct platform_device *pdev) | ||||
| { | ||||
| 	struct atmel_tcb_pwm_chip *tcbpwm = platform_get_drvdata(pdev); | ||||
| 	int err; | ||||
| 
 | ||||
| 	err = pwmchip_remove(&tcbpwm->chip); | ||||
| 	if (err < 0) | ||||
| 		return err; | ||||
| 
 | ||||
| 	atmel_tc_free(tcbpwm->tc); | ||||
| 
 | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| static const struct of_device_id atmel_tcb_pwm_dt_ids[] = { | ||||
| 	{ .compatible = "atmel,tcb-pwm", }, | ||||
| 	{ /* sentinel */ } | ||||
| }; | ||||
| MODULE_DEVICE_TABLE(of, atmel_tcb_pwm_dt_ids); | ||||
| 
 | ||||
| static struct platform_driver atmel_tcb_pwm_driver = { | ||||
| 	.driver = { | ||||
| 		.name = "atmel-tcb-pwm", | ||||
| 		.of_match_table = atmel_tcb_pwm_dt_ids, | ||||
| 	}, | ||||
| 	.probe = atmel_tcb_pwm_probe, | ||||
| 	.remove = atmel_tcb_pwm_remove, | ||||
| }; | ||||
| module_platform_driver(atmel_tcb_pwm_driver); | ||||
| 
 | ||||
| MODULE_AUTHOR("Boris BREZILLON <b.brezillon@overkiz.com>"); | ||||
| MODULE_DESCRIPTION("Atmel Timer Counter Pulse Width Modulation Driver"); | ||||
| MODULE_LICENSE("GPL v2"); | ||||
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	 Boris BREZILLON
						Boris BREZILLON