add basic support for the pwm modul found on imx6. Pieces of this code are based on linux code from drivers/pwm/pwm-imx.c Commit "cd3de83f1476 Linux 3.16-rc4" Signed-off-by: Heiko Schocher <hs@denx.de> Acked-by: Stefano Babic <sbabic@denx.de> Cc: Wolfgang Denk <wd@denx.de>master
parent
aafe4020c1
commit
b2f97cf279
@ -0,0 +1,13 @@ |
|||||||
|
#
|
||||||
|
# (C) Copyright 2006
|
||||||
|
# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
|
||||||
|
#
|
||||||
|
# (C) Copyright 2001
|
||||||
|
# Erik Theisen, Wave 7 Optics, etheisen@mindspring.com.
|
||||||
|
#
|
||||||
|
# SPDX-License-Identifier: GPL-2.0+
|
||||||
|
#
|
||||||
|
|
||||||
|
#ccflags-y += -DDEBUG
|
||||||
|
|
||||||
|
obj-$(CONFIG_PWM_IMX) += pwm-imx.o pwm-imx-util.o
|
@ -0,0 +1,73 @@ |
|||||||
|
/*
|
||||||
|
* (C) Copyright 2014 |
||||||
|
* Heiko Schocher, DENX Software Engineering, hs@denx.de. |
||||||
|
* |
||||||
|
* Basic support for the pwm modul on imx6. |
||||||
|
* |
||||||
|
* Based on linux:drivers/pwm/pwm-imx.c |
||||||
|
* from |
||||||
|
* Sascha Hauer <s.hauer@pengutronix.de> |
||||||
|
* |
||||||
|
* SPDX-License-Identifier: GPL-2.0 |
||||||
|
*/ |
||||||
|
|
||||||
|
#include <common.h> |
||||||
|
#include <div64.h> |
||||||
|
#include <asm/arch/imx-regs.h> |
||||||
|
|
||||||
|
/* pwm_id from 0..3 */ |
||||||
|
struct pwm_regs *pwm_id_to_reg(int pwm_id) |
||||||
|
{ |
||||||
|
switch (pwm_id) { |
||||||
|
case 0: |
||||||
|
return (struct pwm_regs *)PWM1_BASE_ADDR; |
||||||
|
break; |
||||||
|
case 1: |
||||||
|
return (struct pwm_regs *)PWM2_BASE_ADDR; |
||||||
|
break; |
||||||
|
case 2: |
||||||
|
return (struct pwm_regs *)PWM3_BASE_ADDR; |
||||||
|
break; |
||||||
|
case 3: |
||||||
|
return (struct pwm_regs *)PWM4_BASE_ADDR; |
||||||
|
break; |
||||||
|
default: |
||||||
|
printf("unknown pwm_id: %d\n", pwm_id); |
||||||
|
break; |
||||||
|
} |
||||||
|
return NULL; |
||||||
|
} |
||||||
|
|
||||||
|
int pwm_imx_get_parms(int period_ns, int duty_ns, unsigned long *period_c, |
||||||
|
unsigned long *duty_c, unsigned long *prescale) |
||||||
|
{ |
||||||
|
unsigned long long c; |
||||||
|
|
||||||
|
/*
|
||||||
|
* we have not yet a clock framework for imx6, so add the clock |
||||||
|
* value here as a define. Replace it when we have the clock |
||||||
|
* framework. |
||||||
|
*/ |
||||||
|
c = CONFIG_IMX6_PWM_PER_CLK; |
||||||
|
c = c * period_ns; |
||||||
|
do_div(c, 1000000000); |
||||||
|
*period_c = c; |
||||||
|
|
||||||
|
*prescale = *period_c / 0x10000 + 1; |
||||||
|
|
||||||
|
*period_c /= *prescale; |
||||||
|
c = (unsigned long long)(*period_c * duty_ns); |
||||||
|
do_div(c, period_ns); |
||||||
|
*duty_c = c; |
||||||
|
|
||||||
|
/*
|
||||||
|
* according to imx pwm RM, the real period value should be |
||||||
|
* PERIOD value in PWMPR plus 2. |
||||||
|
*/ |
||||||
|
if (*period_c > 2) |
||||||
|
*period_c -= 2; |
||||||
|
else |
||||||
|
*period_c = 0; |
||||||
|
|
||||||
|
return 0; |
||||||
|
} |
@ -0,0 +1,16 @@ |
|||||||
|
/*
|
||||||
|
* (C) Copyright 2014 |
||||||
|
* Heiko Schocher, DENX Software Engineering, hs@denx.de. |
||||||
|
* |
||||||
|
* Basic support for the pwm modul on imx6. |
||||||
|
* |
||||||
|
* SPDX-License-Identifier: GPL-2.0 |
||||||
|
*/ |
||||||
|
|
||||||
|
#ifndef _pwm_imx_util_h_ |
||||||
|
#define _pwm_imx_util_h_ |
||||||
|
|
||||||
|
struct pwm_regs *pwm_id_to_reg(int pwm_id); |
||||||
|
int pwm_imx_get_parms(int period_ns, int duty_ns, unsigned long *period_c, |
||||||
|
unsigned long *duty_c, unsigned long *prescale); |
||||||
|
#endif |
@ -0,0 +1,59 @@ |
|||||||
|
/*
|
||||||
|
* (C) Copyright 2014 |
||||||
|
* Heiko Schocher, DENX Software Engineering, hs@denx.de. |
||||||
|
* |
||||||
|
* Basic support for the pwm modul on imx6. |
||||||
|
* |
||||||
|
* SPDX-License-Identifier: GPL-2.0+ |
||||||
|
*/ |
||||||
|
|
||||||
|
#include <common.h> |
||||||
|
#include <div64.h> |
||||||
|
#include <pwm.h> |
||||||
|
#include <asm/arch/imx-regs.h> |
||||||
|
#include <asm/io.h> |
||||||
|
#include "pwm-imx-util.h" |
||||||
|
|
||||||
|
int pwm_init(int pwm_id, int div, int invert) |
||||||
|
{ |
||||||
|
struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id); |
||||||
|
|
||||||
|
writel(0, &pwm->ir); |
||||||
|
return 0; |
||||||
|
} |
||||||
|
|
||||||
|
int pwm_config(int pwm_id, int duty_ns, int period_ns) |
||||||
|
{ |
||||||
|
struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id); |
||||||
|
unsigned long period_cycles, duty_cycles, prescale; |
||||||
|
u32 cr; |
||||||
|
|
||||||
|
pwm_imx_get_parms(period_ns, duty_ns, &period_cycles, &duty_cycles, |
||||||
|
&prescale); |
||||||
|
|
||||||
|
cr = PWMCR_PRESCALER(prescale) | |
||||||
|
PWMCR_DOZEEN | PWMCR_WAITEN | |
||||||
|
PWMCR_DBGEN | PWMCR_CLKSRC_IPG_HIGH; |
||||||
|
|
||||||
|
writel(cr, &pwm->cr); |
||||||
|
/* set duty cycles */ |
||||||
|
writel(duty_cycles, &pwm->sar); |
||||||
|
/* set period cycles */ |
||||||
|
writel(period_cycles, &pwm->pr); |
||||||
|
return 0; |
||||||
|
} |
||||||
|
|
||||||
|
int pwm_enable(int pwm_id) |
||||||
|
{ |
||||||
|
struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id); |
||||||
|
|
||||||
|
setbits_le32(&pwm->cr, PWMCR_EN); |
||||||
|
return 0; |
||||||
|
} |
||||||
|
|
||||||
|
void pwm_disable(int pwm_id) |
||||||
|
{ |
||||||
|
struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id); |
||||||
|
|
||||||
|
clrbits_le32(&pwm->cr, PWMCR_EN); |
||||||
|
} |
Loading…
Reference in new issue