forked from mirrors/linux
		
	pwm: pwm-tiehrpwm: PWM driver support for EHRPWM
Enhanced high resolution PWM module (EHRPWM) hardware can be used to generate PWM output over 2 channels. This commit adds PWM driver support for EHRPWM device present on AM33XX SOC. Current implementation supports simple PWM functionality. Reviewed-by: Vaibhav Bedia <vaibhav.bedia@ti.com> Signed-off-by: Philip, Avinash <avinashphilip@ti.com> Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
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		|  | @ -86,6 +86,16 @@ config  PWM_TIECAP | ||||||
| 	  To compile this driver as a module, choose M here: the module | 	  To compile this driver as a module, choose M here: the module | ||||||
| 	  will be called pwm-tiecap. | 	  will be called pwm-tiecap. | ||||||
| 
 | 
 | ||||||
|  | config  PWM_TIEHRPWM | ||||||
|  | 	tristate "EHRPWM PWM support" | ||||||
|  | 	depends on SOC_AM33XX | ||||||
|  | 	help | ||||||
|  | 	  PWM driver support for the EHRPWM controller found on AM33XX | ||||||
|  | 	  TI SOC | ||||||
|  | 
 | ||||||
|  | 	  To compile this driver as a module, choose M here: the module | ||||||
|  | 	  will be called pwm-tiehrpwm. | ||||||
|  | 
 | ||||||
| config PWM_VT8500 | config PWM_VT8500 | ||||||
| 	tristate "vt8500 pwm support" | 	tristate "vt8500 pwm support" | ||||||
| 	depends on ARCH_VT8500 | 	depends on ARCH_VT8500 | ||||||
|  |  | ||||||
|  | @ -7,4 +7,5 @@ obj-$(CONFIG_PWM_PXA)		+= pwm-pxa.o | ||||||
| obj-$(CONFIG_PWM_SAMSUNG)	+= pwm-samsung.o | obj-$(CONFIG_PWM_SAMSUNG)	+= pwm-samsung.o | ||||||
| obj-$(CONFIG_PWM_TEGRA)		+= pwm-tegra.o | obj-$(CONFIG_PWM_TEGRA)		+= pwm-tegra.o | ||||||
| obj-$(CONFIG_PWM_TIECAP)	+= pwm-tiecap.o | obj-$(CONFIG_PWM_TIECAP)	+= pwm-tiecap.o | ||||||
|  | obj-$(CONFIG_PWM_TIEHRPWM)	+= pwm-tiehrpwm.o | ||||||
| obj-$(CONFIG_PWM_VT8500)	+= pwm-vt8500.o | obj-$(CONFIG_PWM_VT8500)	+= pwm-vt8500.o | ||||||
|  |  | ||||||
							
								
								
									
										411
									
								
								drivers/pwm/pwm-tiehrpwm.c
									
									
									
									
									
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										411
									
								
								drivers/pwm/pwm-tiehrpwm.c
									
									
									
									
									
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							|  | @ -0,0 +1,411 @@ | ||||||
|  | /*
 | ||||||
|  |  * EHRPWM PWM driver | ||||||
|  |  * | ||||||
|  |  * Copyright (C) 2012 Texas Instruments, Inc. - http://www.ti.com/
 | ||||||
|  |  * | ||||||
|  |  * This program is free software; you can redistribute it and/or modify | ||||||
|  |  * it under the terms of the GNU General Public License as published by | ||||||
|  |  * the Free Software Foundation; either version 2 of the License, or | ||||||
|  |  * (at your option) any later version. | ||||||
|  |  * | ||||||
|  |  * This program is distributed in the hope that it will be useful, | ||||||
|  |  * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||||||
|  |  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||||||
|  |  * GNU General Public License for more details. | ||||||
|  |  * | ||||||
|  |  * You should have received a copy of the GNU General Public License | ||||||
|  |  * along with this program; if not, write to the Free Software | ||||||
|  |  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | ||||||
|  |  */ | ||||||
|  | 
 | ||||||
|  | #include <linux/module.h> | ||||||
|  | #include <linux/platform_device.h> | ||||||
|  | #include <linux/pwm.h> | ||||||
|  | #include <linux/io.h> | ||||||
|  | #include <linux/err.h> | ||||||
|  | #include <linux/clk.h> | ||||||
|  | #include <linux/pm_runtime.h> | ||||||
|  | 
 | ||||||
|  | /* EHRPWM registers and bits definitions */ | ||||||
|  | 
 | ||||||
|  | /* Time base module registers */ | ||||||
|  | #define TBCTL			0x00 | ||||||
|  | #define TBPRD			0x0A | ||||||
|  | 
 | ||||||
|  | #define TBCTL_RUN_MASK		(BIT(15) | BIT(14)) | ||||||
|  | #define TBCTL_STOP_NEXT		0 | ||||||
|  | #define TBCTL_STOP_ON_CYCLE	BIT(14) | ||||||
|  | #define TBCTL_FREE_RUN		(BIT(15) | BIT(14)) | ||||||
|  | #define TBCTL_PRDLD_MASK	BIT(3) | ||||||
|  | #define TBCTL_PRDLD_SHDW	0 | ||||||
|  | #define TBCTL_PRDLD_IMDT	BIT(3) | ||||||
|  | #define TBCTL_CLKDIV_MASK	(BIT(12) | BIT(11) | BIT(10) | BIT(9) | \ | ||||||
|  | 				BIT(8) | BIT(7)) | ||||||
|  | #define TBCTL_CTRMODE_MASK	(BIT(1) | BIT(0)) | ||||||
|  | #define TBCTL_CTRMODE_UP	0 | ||||||
|  | #define TBCTL_CTRMODE_DOWN	BIT(0) | ||||||
|  | #define TBCTL_CTRMODE_UPDOWN	BIT(1) | ||||||
|  | #define TBCTL_CTRMODE_FREEZE	(BIT(1) | BIT(0)) | ||||||
|  | 
 | ||||||
|  | #define TBCTL_HSPCLKDIV_SHIFT	7 | ||||||
|  | #define TBCTL_CLKDIV_SHIFT	10 | ||||||
|  | 
 | ||||||
|  | #define CLKDIV_MAX		7 | ||||||
|  | #define HSPCLKDIV_MAX		7 | ||||||
|  | #define PERIOD_MAX		0xFFFF | ||||||
|  | 
 | ||||||
|  | /* compare module registers */ | ||||||
|  | #define CMPA			0x12 | ||||||
|  | #define CMPB			0x14 | ||||||
|  | 
 | ||||||
|  | /* Action qualifier module registers */ | ||||||
|  | #define AQCTLA			0x16 | ||||||
|  | #define AQCTLB			0x18 | ||||||
|  | #define AQSFRC			0x1A | ||||||
|  | #define AQCSFRC			0x1C | ||||||
|  | 
 | ||||||
|  | #define AQCTL_CBU_MASK		(BIT(9) | BIT(8)) | ||||||
|  | #define AQCTL_CBU_FRCLOW	BIT(8) | ||||||
|  | #define AQCTL_CBU_FRCHIGH	BIT(9) | ||||||
|  | #define AQCTL_CBU_FRCTOGGLE	(BIT(9) | BIT(8)) | ||||||
|  | #define AQCTL_CAU_MASK		(BIT(5) | BIT(4)) | ||||||
|  | #define AQCTL_CAU_FRCLOW	BIT(4) | ||||||
|  | #define AQCTL_CAU_FRCHIGH	BIT(5) | ||||||
|  | #define AQCTL_CAU_FRCTOGGLE	(BIT(5) | BIT(4)) | ||||||
|  | #define AQCTL_PRD_MASK		(BIT(3) | BIT(2)) | ||||||
|  | #define AQCTL_PRD_FRCLOW	BIT(2) | ||||||
|  | #define AQCTL_PRD_FRCHIGH	BIT(3) | ||||||
|  | #define AQCTL_PRD_FRCTOGGLE	(BIT(3) | BIT(2)) | ||||||
|  | #define AQCTL_ZRO_MASK		(BIT(1) | BIT(0)) | ||||||
|  | #define AQCTL_ZRO_FRCLOW	BIT(0) | ||||||
|  | #define AQCTL_ZRO_FRCHIGH	BIT(1) | ||||||
|  | #define AQCTL_ZRO_FRCTOGGLE	(BIT(1) | BIT(0)) | ||||||
|  | 
 | ||||||
|  | #define AQSFRC_RLDCSF_MASK	(BIT(7) | BIT(6)) | ||||||
|  | #define AQSFRC_RLDCSF_ZRO	0 | ||||||
|  | #define AQSFRC_RLDCSF_PRD	BIT(6) | ||||||
|  | #define AQSFRC_RLDCSF_ZROPRD	BIT(7) | ||||||
|  | #define AQSFRC_RLDCSF_IMDT	(BIT(7) | BIT(6)) | ||||||
|  | 
 | ||||||
|  | #define AQCSFRC_CSFB_MASK	(BIT(3) | BIT(2)) | ||||||
|  | #define AQCSFRC_CSFB_FRCDIS	0 | ||||||
|  | #define AQCSFRC_CSFB_FRCLOW	BIT(2) | ||||||
|  | #define AQCSFRC_CSFB_FRCHIGH	BIT(3) | ||||||
|  | #define AQCSFRC_CSFB_DISSWFRC	(BIT(3) | BIT(2)) | ||||||
|  | #define AQCSFRC_CSFA_MASK	(BIT(1) | BIT(0)) | ||||||
|  | #define AQCSFRC_CSFA_FRCDIS	0 | ||||||
|  | #define AQCSFRC_CSFA_FRCLOW	BIT(0) | ||||||
|  | #define AQCSFRC_CSFA_FRCHIGH	BIT(1) | ||||||
|  | #define AQCSFRC_CSFA_DISSWFRC	(BIT(1) | BIT(0)) | ||||||
|  | 
 | ||||||
|  | #define NUM_PWM_CHANNEL		2	/* EHRPWM channels */ | ||||||
|  | 
 | ||||||
|  | struct ehrpwm_pwm_chip { | ||||||
|  | 	struct pwm_chip	chip; | ||||||
|  | 	unsigned int	clk_rate; | ||||||
|  | 	void __iomem	*mmio_base; | ||||||
|  | }; | ||||||
|  | 
 | ||||||
|  | static inline struct ehrpwm_pwm_chip *to_ehrpwm_pwm_chip(struct pwm_chip *chip) | ||||||
|  | { | ||||||
|  | 	return container_of(chip, struct ehrpwm_pwm_chip, chip); | ||||||
|  | } | ||||||
|  | 
 | ||||||
|  | static void ehrpwm_write(void *base, int offset, unsigned int val) | ||||||
|  | { | ||||||
|  | 	writew(val & 0xFFFF, base + offset); | ||||||
|  | } | ||||||
|  | 
 | ||||||
|  | static void ehrpwm_modify(void *base, int offset, | ||||||
|  | 		unsigned short mask, unsigned short val) | ||||||
|  | { | ||||||
|  | 	unsigned short regval; | ||||||
|  | 
 | ||||||
|  | 	regval = readw(base + offset); | ||||||
|  | 	regval &= ~mask; | ||||||
|  | 	regval |= val & mask; | ||||||
|  | 	writew(regval, base + offset); | ||||||
|  | } | ||||||
|  | 
 | ||||||
|  | /**
 | ||||||
|  |  * set_prescale_div -	Set up the prescaler divider function | ||||||
|  |  * @rqst_prescaler:	prescaler value min | ||||||
|  |  * @prescale_div:	prescaler value set | ||||||
|  |  * @tb_clk_div:		Time Base Control prescaler bits | ||||||
|  |  */ | ||||||
|  | static int set_prescale_div(unsigned long rqst_prescaler, | ||||||
|  | 		unsigned short *prescale_div, unsigned short *tb_clk_div) | ||||||
|  | { | ||||||
|  | 	unsigned int clkdiv, hspclkdiv; | ||||||
|  | 
 | ||||||
|  | 	for (clkdiv = 0; clkdiv <= CLKDIV_MAX; clkdiv++) { | ||||||
|  | 		for (hspclkdiv = 0; hspclkdiv <= HSPCLKDIV_MAX; hspclkdiv++) { | ||||||
|  | 
 | ||||||
|  | 			/*
 | ||||||
|  | 			 * calculations for prescaler value : | ||||||
|  | 			 * prescale_div = HSPCLKDIVIDER * CLKDIVIDER. | ||||||
|  | 			 * HSPCLKDIVIDER =  2 ** hspclkdiv | ||||||
|  | 			 * CLKDIVIDER = (1),		if clkdiv == 0 *OR* | ||||||
|  | 			 *		(2 * clkdiv),	if clkdiv != 0 | ||||||
|  | 			 * | ||||||
|  | 			 * Configure prescale_div value such that period | ||||||
|  | 			 * register value is less than 65535. | ||||||
|  | 			 */ | ||||||
|  | 
 | ||||||
|  | 			*prescale_div = (1 << clkdiv) * | ||||||
|  | 					(hspclkdiv ? (hspclkdiv * 2) : 1); | ||||||
|  | 			if (*prescale_div > rqst_prescaler) { | ||||||
|  | 				*tb_clk_div = (clkdiv << TBCTL_CLKDIV_SHIFT) | | ||||||
|  | 					(hspclkdiv << TBCTL_HSPCLKDIV_SHIFT); | ||||||
|  | 				return 0; | ||||||
|  | 			} | ||||||
|  | 		} | ||||||
|  | 	} | ||||||
|  | 	return 1; | ||||||
|  | } | ||||||
|  | 
 | ||||||
|  | static void configure_chans(struct ehrpwm_pwm_chip *pc, int chan, | ||||||
|  | 		unsigned long duty_cycles) | ||||||
|  | { | ||||||
|  | 	int cmp_reg, aqctl_reg; | ||||||
|  | 	unsigned short aqctl_val, aqctl_mask; | ||||||
|  | 
 | ||||||
|  | 	/*
 | ||||||
|  | 	 * Channels can be configured from action qualifier module. | ||||||
|  | 	 * Channel 0 configured with compare A register and for | ||||||
|  | 	 * up-counter mode. | ||||||
|  | 	 * Channel 1 configured with compare B register and for | ||||||
|  | 	 * up-counter mode. | ||||||
|  | 	 */ | ||||||
|  | 	if (chan == 1) { | ||||||
|  | 		aqctl_reg = AQCTLB; | ||||||
|  | 		cmp_reg = CMPB; | ||||||
|  | 		/* Configure PWM Low from compare B value */ | ||||||
|  | 		aqctl_val = AQCTL_CBU_FRCLOW; | ||||||
|  | 		aqctl_mask = AQCTL_CBU_MASK; | ||||||
|  | 	} else { | ||||||
|  | 		cmp_reg = CMPA; | ||||||
|  | 		aqctl_reg = AQCTLA; | ||||||
|  | 		/* Configure PWM Low from compare A value*/ | ||||||
|  | 		aqctl_val = AQCTL_CAU_FRCLOW; | ||||||
|  | 		aqctl_mask = AQCTL_CAU_MASK; | ||||||
|  | 	} | ||||||
|  | 
 | ||||||
|  | 	/* Configure PWM High from period value and zero value */ | ||||||
|  | 	aqctl_val |= AQCTL_PRD_FRCHIGH | AQCTL_ZRO_FRCHIGH; | ||||||
|  | 	aqctl_mask |= AQCTL_PRD_MASK | AQCTL_ZRO_MASK; | ||||||
|  | 	ehrpwm_modify(pc->mmio_base,  aqctl_reg, aqctl_mask, aqctl_val); | ||||||
|  | 
 | ||||||
|  | 	ehrpwm_write(pc->mmio_base,  cmp_reg, duty_cycles); | ||||||
|  | } | ||||||
|  | 
 | ||||||
|  | /*
 | ||||||
|  |  * period_ns = 10^9 * (ps_divval * period_cycles) / PWM_CLK_RATE | ||||||
|  |  * duty_ns   = 10^9 * (ps_divval * duty_cycles) / PWM_CLK_RATE | ||||||
|  |  */ | ||||||
|  | static int ehrpwm_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, | ||||||
|  | 		int duty_ns, int period_ns) | ||||||
|  | { | ||||||
|  | 	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip); | ||||||
|  | 	unsigned long long c; | ||||||
|  | 	unsigned long period_cycles, duty_cycles; | ||||||
|  | 	unsigned short ps_divval, tb_divval; | ||||||
|  | 
 | ||||||
|  | 	if (period_ns < 0 || duty_ns < 0 || period_ns > NSEC_PER_SEC) | ||||||
|  | 		return -ERANGE; | ||||||
|  | 
 | ||||||
|  | 	c = pc->clk_rate; | ||||||
|  | 	c = c * period_ns; | ||||||
|  | 	do_div(c, NSEC_PER_SEC); | ||||||
|  | 	period_cycles = (unsigned long)c; | ||||||
|  | 
 | ||||||
|  | 	if (period_cycles < 1) { | ||||||
|  | 		period_cycles = 1; | ||||||
|  | 		duty_cycles = 1; | ||||||
|  | 	} else { | ||||||
|  | 		c = pc->clk_rate; | ||||||
|  | 		c = c * duty_ns; | ||||||
|  | 		do_div(c, NSEC_PER_SEC); | ||||||
|  | 		duty_cycles = (unsigned long)c; | ||||||
|  | 	} | ||||||
|  | 
 | ||||||
|  | 	/* Configure clock prescaler to support Low frequency PWM wave */ | ||||||
|  | 	if (set_prescale_div(period_cycles/PERIOD_MAX, &ps_divval, | ||||||
|  | 				&tb_divval)) { | ||||||
|  | 		dev_err(chip->dev, "Unsupported values\n"); | ||||||
|  | 		return -EINVAL; | ||||||
|  | 	} | ||||||
|  | 
 | ||||||
|  | 	pm_runtime_get_sync(chip->dev); | ||||||
|  | 
 | ||||||
|  | 	/* Update clock prescaler values */ | ||||||
|  | 	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_CLKDIV_MASK, tb_divval); | ||||||
|  | 
 | ||||||
|  | 	/* Update period & duty cycle with presacler division */ | ||||||
|  | 	period_cycles = period_cycles / ps_divval; | ||||||
|  | 	duty_cycles = duty_cycles / ps_divval; | ||||||
|  | 
 | ||||||
|  | 	/* Configure shadow loading on Period register */ | ||||||
|  | 	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_PRDLD_MASK, TBCTL_PRDLD_SHDW); | ||||||
|  | 
 | ||||||
|  | 	ehrpwm_write(pc->mmio_base, TBPRD, period_cycles); | ||||||
|  | 
 | ||||||
|  | 	/* Configure ehrpwm counter for up-count mode */ | ||||||
|  | 	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_CTRMODE_MASK, | ||||||
|  | 			TBCTL_CTRMODE_UP); | ||||||
|  | 
 | ||||||
|  | 	/* Configure the channel for duty cycle */ | ||||||
|  | 	configure_chans(pc, pwm->hwpwm, duty_cycles); | ||||||
|  | 	pm_runtime_put_sync(chip->dev); | ||||||
|  | 	return 0; | ||||||
|  | } | ||||||
|  | 
 | ||||||
|  | static int ehrpwm_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) | ||||||
|  | { | ||||||
|  | 	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip); | ||||||
|  | 	unsigned short aqcsfrc_val, aqcsfrc_mask; | ||||||
|  | 
 | ||||||
|  | 	/* Leave clock enabled on enabling PWM */ | ||||||
|  | 	pm_runtime_get_sync(chip->dev); | ||||||
|  | 
 | ||||||
|  | 	/* Disabling Action Qualifier on PWM output */ | ||||||
|  | 	if (pwm->hwpwm) { | ||||||
|  | 		aqcsfrc_val = AQCSFRC_CSFB_FRCDIS; | ||||||
|  | 		aqcsfrc_mask = AQCSFRC_CSFB_MASK; | ||||||
|  | 	} else { | ||||||
|  | 		aqcsfrc_val = AQCSFRC_CSFA_FRCDIS; | ||||||
|  | 		aqcsfrc_mask = AQCSFRC_CSFA_MASK; | ||||||
|  | 	} | ||||||
|  | 
 | ||||||
|  | 	/* Changes to shadow mode */ | ||||||
|  | 	ehrpwm_modify(pc->mmio_base, AQSFRC, AQSFRC_RLDCSF_MASK, | ||||||
|  | 			AQSFRC_RLDCSF_ZRO); | ||||||
|  | 
 | ||||||
|  | 	ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val); | ||||||
|  | 
 | ||||||
|  | 	/* Enable time counter for free_run */ | ||||||
|  | 	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_RUN_MASK, TBCTL_FREE_RUN); | ||||||
|  | 	return 0; | ||||||
|  | } | ||||||
|  | 
 | ||||||
|  | static void ehrpwm_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) | ||||||
|  | { | ||||||
|  | 	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip); | ||||||
|  | 	unsigned short aqcsfrc_val, aqcsfrc_mask; | ||||||
|  | 
 | ||||||
|  | 	/* Action Qualifier puts PWM output low forcefully */ | ||||||
|  | 	if (pwm->hwpwm) { | ||||||
|  | 		aqcsfrc_val = AQCSFRC_CSFB_FRCLOW; | ||||||
|  | 		aqcsfrc_mask = AQCSFRC_CSFB_MASK; | ||||||
|  | 	} else { | ||||||
|  | 		aqcsfrc_val = AQCSFRC_CSFA_FRCLOW; | ||||||
|  | 		aqcsfrc_mask = AQCSFRC_CSFA_MASK; | ||||||
|  | 	} | ||||||
|  | 
 | ||||||
|  | 	/*
 | ||||||
|  | 	 * Changes to immediate action on Action Qualifier. This puts | ||||||
|  | 	 * Action Qualifier control on PWM output from next TBCLK | ||||||
|  | 	 */ | ||||||
|  | 	ehrpwm_modify(pc->mmio_base, AQSFRC, AQSFRC_RLDCSF_MASK, | ||||||
|  | 			AQSFRC_RLDCSF_IMDT); | ||||||
|  | 
 | ||||||
|  | 	ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val); | ||||||
|  | 
 | ||||||
|  | 	/* Stop Time base counter */ | ||||||
|  | 	ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_RUN_MASK, TBCTL_STOP_NEXT); | ||||||
|  | 
 | ||||||
|  | 	/* Disable clock on PWM disable */ | ||||||
|  | 	pm_runtime_put_sync(chip->dev); | ||||||
|  | } | ||||||
|  | 
 | ||||||
|  | static void ehrpwm_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) | ||||||
|  | { | ||||||
|  | 	if (test_bit(PWMF_ENABLED, &pwm->flags)) { | ||||||
|  | 		dev_warn(chip->dev, "Removing PWM device without disabling\n"); | ||||||
|  | 		pm_runtime_put_sync(chip->dev); | ||||||
|  | 	} | ||||||
|  | } | ||||||
|  | 
 | ||||||
|  | static const struct pwm_ops ehrpwm_pwm_ops = { | ||||||
|  | 	.free		= ehrpwm_pwm_free, | ||||||
|  | 	.config		= ehrpwm_pwm_config, | ||||||
|  | 	.enable		= ehrpwm_pwm_enable, | ||||||
|  | 	.disable	= ehrpwm_pwm_disable, | ||||||
|  | 	.owner		= THIS_MODULE, | ||||||
|  | }; | ||||||
|  | 
 | ||||||
|  | static int __devinit ehrpwm_pwm_probe(struct platform_device *pdev) | ||||||
|  | { | ||||||
|  | 	int ret; | ||||||
|  | 	struct resource *r; | ||||||
|  | 	struct clk *clk; | ||||||
|  | 	struct ehrpwm_pwm_chip *pc; | ||||||
|  | 
 | ||||||
|  | 	pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL); | ||||||
|  | 	if (!pc) { | ||||||
|  | 		dev_err(&pdev->dev, "failed to allocate memory\n"); | ||||||
|  | 		return -ENOMEM; | ||||||
|  | 	} | ||||||
|  | 
 | ||||||
|  | 	clk = devm_clk_get(&pdev->dev, "fck"); | ||||||
|  | 	if (IS_ERR(clk)) { | ||||||
|  | 		dev_err(&pdev->dev, "failed to get clock\n"); | ||||||
|  | 		return PTR_ERR(clk); | ||||||
|  | 	} | ||||||
|  | 
 | ||||||
|  | 	pc->clk_rate = clk_get_rate(clk); | ||||||
|  | 	if (!pc->clk_rate) { | ||||||
|  | 		dev_err(&pdev->dev, "failed to get clock rate\n"); | ||||||
|  | 		return -EINVAL; | ||||||
|  | 	} | ||||||
|  | 
 | ||||||
|  | 	pc->chip.dev = &pdev->dev; | ||||||
|  | 	pc->chip.ops = &ehrpwm_pwm_ops; | ||||||
|  | 	pc->chip.base = -1; | ||||||
|  | 	pc->chip.npwm = NUM_PWM_CHANNEL; | ||||||
|  | 
 | ||||||
|  | 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0); | ||||||
|  | 	if (!r) { | ||||||
|  | 		dev_err(&pdev->dev, "no memory resource defined\n"); | ||||||
|  | 		return -ENODEV; | ||||||
|  | 	} | ||||||
|  | 
 | ||||||
|  | 	pc->mmio_base = devm_request_and_ioremap(&pdev->dev, r); | ||||||
|  | 	if (!pc->mmio_base) { | ||||||
|  | 		dev_err(&pdev->dev, "failed to ioremap() registers\n"); | ||||||
|  | 		return  -EADDRNOTAVAIL; | ||||||
|  | 	} | ||||||
|  | 
 | ||||||
|  | 	ret = pwmchip_add(&pc->chip); | ||||||
|  | 	if (ret < 0) { | ||||||
|  | 		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret); | ||||||
|  | 		return ret; | ||||||
|  | 	} | ||||||
|  | 
 | ||||||
|  | 	pm_runtime_enable(&pdev->dev); | ||||||
|  | 	platform_set_drvdata(pdev, pc); | ||||||
|  | 	return 0; | ||||||
|  | } | ||||||
|  | 
 | ||||||
|  | static int __devexit ehrpwm_pwm_remove(struct platform_device *pdev) | ||||||
|  | { | ||||||
|  | 	struct ehrpwm_pwm_chip *pc = platform_get_drvdata(pdev); | ||||||
|  | 
 | ||||||
|  | 	pm_runtime_put_sync(&pdev->dev); | ||||||
|  | 	pm_runtime_disable(&pdev->dev); | ||||||
|  | 	return pwmchip_remove(&pc->chip); | ||||||
|  | } | ||||||
|  | 
 | ||||||
|  | static struct platform_driver ehrpwm_pwm_driver = { | ||||||
|  | 	.driver = { | ||||||
|  | 		.name = "ehrpwm", | ||||||
|  | 	}, | ||||||
|  | 	.probe = ehrpwm_pwm_probe, | ||||||
|  | 	.remove = __devexit_p(ehrpwm_pwm_remove), | ||||||
|  | }; | ||||||
|  | 
 | ||||||
|  | module_platform_driver(ehrpwm_pwm_driver); | ||||||
|  | 
 | ||||||
|  | MODULE_DESCRIPTION("EHRPWM PWM driver"); | ||||||
|  | MODULE_AUTHOR("Texas Instruments"); | ||||||
|  | MODULE_LICENSE("GPL"); | ||||||
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		Reference in a new issue
	
	 Philip, Avinash
						Philip, Avinash