diff options
| -rw-r--r-- | arch/arm/mach-pxa/Makefile | 1 | ||||
| -rw-r--r-- | arch/arm/mach-pxa/devices.c | 5 | ||||
| -rw-r--r-- | arch/arm/mach-pxa/include/mach/clock.h | 1 | ||||
| -rw-r--r-- | arch/arm/mach-pxa/include/mach/devices.h | 2 | ||||
| -rw-r--r-- | arch/arm/mach-pxa/include/mach/regs-pwm.h | 20 | ||||
| -rw-r--r-- | arch/arm/mach-pxa/speed-pxa27x.c | 5 | ||||
| -rw-r--r-- | drivers/pwm/Kconfig | 6 | ||||
| -rw-r--r-- | drivers/pwm/Makefile | 1 | ||||
| -rw-r--r-- | drivers/pwm/pxa_pwm.c | 157 |
9 files changed, 197 insertions, 1 deletions
diff --git a/arch/arm/mach-pxa/Makefile b/arch/arm/mach-pxa/Makefile index c01a9e0281..6a02a5459c 100644 --- a/arch/arm/mach-pxa/Makefile +++ b/arch/arm/mach-pxa/Makefile @@ -1,6 +1,7 @@ obj-y += clocksource.o obj-y += common.o obj-y += gpio.o +obj-y += devices.o obj-$(CONFIG_ARCH_PXA2XX) += mfp-pxa2xx.o obj-$(CONFIG_ARCH_PXA27X) += speed-pxa27x.o diff --git a/arch/arm/mach-pxa/devices.c b/arch/arm/mach-pxa/devices.c index 1a396f1258..b6ac0ba621 100644 --- a/arch/arm/mach-pxa/devices.c +++ b/arch/arm/mach-pxa/devices.c @@ -47,3 +47,8 @@ struct device_d *pxa_add_mmc(void *base, int id, void *pdata) { return pxa_add_device("pxa-mmc", id, base, 0x1000, pdata); } + +struct device_d *pxa_add_pwm(void *base, int id) +{ + return pxa_add_device("pxa_pwm", id, base, 0x10, NULL); +} diff --git a/arch/arm/mach-pxa/include/mach/clock.h b/arch/arm/mach-pxa/include/mach/clock.h index c53432f015..f86152f7af 100644 --- a/arch/arm/mach-pxa/include/mach/clock.h +++ b/arch/arm/mach-pxa/include/mach/clock.h @@ -14,5 +14,6 @@ unsigned long pxa_get_uartclk(void); unsigned long pxa_get_mmcclk(void); unsigned long pxa_get_lcdclk(void); +unsigned long pxa_get_pwmclk(void); #endif /* !__MACH_CLOCK_H */ diff --git a/arch/arm/mach-pxa/include/mach/devices.h b/arch/arm/mach-pxa/include/mach/devices.h index e205b7c7f2..8390153864 100644 --- a/arch/arm/mach-pxa/include/mach/devices.h +++ b/arch/arm/mach-pxa/include/mach/devices.h @@ -23,4 +23,4 @@ struct device_d *pxa_add_i2c(void *base, int id, struct device_d *pxa_add_uart(void *base, int id); struct device_d *pxa_add_fb(void *base, struct pxafb_platform_data *pdata); struct device_d *pxa_add_mmc(void *base, int id, void *pdata); - +struct device_d *pxa_add_pwm(void *base, int id); diff --git a/arch/arm/mach-pxa/include/mach/regs-pwm.h b/arch/arm/mach-pxa/include/mach/regs-pwm.h new file mode 100644 index 0000000000..9fdcbb64ae --- /dev/null +++ b/arch/arm/mach-pxa/include/mach/regs-pwm.h @@ -0,0 +1,20 @@ +/* + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#ifndef __ASM_MACH_REGS_PWM_H +#define __ASM_MACH_REGS_PWM_H + +#include <mach/hardware.h> + +/* + * Pulse modulator registers + */ +#define PWM0 0x40B00000 +#define PWM1 0x40C00000 +#define PWM0slave 0x40B00010 +#define PWM1slave 0x40C00010 + +#endif diff --git a/arch/arm/mach-pxa/speed-pxa27x.c b/arch/arm/mach-pxa/speed-pxa27x.c index 534eb1dcc7..1de034c677 100644 --- a/arch/arm/mach-pxa/speed-pxa27x.c +++ b/arch/arm/mach-pxa/speed-pxa27x.c @@ -47,3 +47,8 @@ unsigned long pxa_get_lcdclk(void) { return pxa_get_lcdclk_10khz() * 10000; } + +unsigned long pxa_get_pwmclk(void) +{ + return BASE_CLK; +} diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 93c1052291..50c956a67d 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -8,5 +8,11 @@ menuconfig PWM If unsure, say N. if PWM +config PWM_PXA + bool "PXA PWM Support" + default y if ARCH_PXA2XX + help + This enables PWM support for Intel/Marvell PXA chips, such + as the PXA25x, PXA27x. endif diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index 3469c3d28b..c886bd55bf 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -1 +1,2 @@ obj-$(CONFIG_PWM) += core.o +obj-$(CONFIG_PWM_PXA) += pxa_pwm.o
\ No newline at end of file diff --git a/drivers/pwm/pxa_pwm.c b/drivers/pwm/pxa_pwm.c new file mode 100644 index 0000000000..cf1f96a10a --- /dev/null +++ b/drivers/pwm/pxa_pwm.c @@ -0,0 +1,157 @@ +/* + * simple driver for PWM (Pulse Width Modulator) controller + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * 2008-02-13 initial version eric miao <eric.miao@marvell.com> + * 2012 Robert Jarzmik <robert.jarzmik@free.fr> + */ + +#include <common.h> +#include <init.h> +#include <errno.h> +#include <io.h> +#include <pwm.h> + +#include <mach/hardware.h> +#include <mach/clock.h> +#include <mach/pxa-regs.h> +#include <mach/regs-pwm.h> +#include <asm-generic/div64.h> +#include <linux/compiler.h> + +/* PWM registers and bits definitions */ +#define PWMCR (0x00) +#define PWMDCR (0x04) +#define PWMPCR (0x08) + +#define PWMCR_SD (1 << 6) +#define PWMDCR_FD (1 << 10) + +struct pxa_pwm_chip { + struct pwm_chip chip; + void __iomem *iobase; + int id; + int duty_ns; + int period_ns; +}; + +static struct pxa_pwm_chip *to_pxa_pwm_chip(struct pwm_chip *chip) +{ + return container_of(chip, struct pxa_pwm_chip, chip); +} + +/* + * period_ns = 10^9 * (PRESCALE + 1) * (PV + 1) / PWM_CLK_RATE + * duty_ns = 10^9 * (PRESCALE + 1) * DC / PWM_CLK_RATE + * PWM_CLK_RATE = 13 MHz + */ +static int pxa_pwm_config(struct pwm_chip *chip, int duty_ns, int period_ns) +{ + unsigned long long c; + unsigned long period_cycles, prescale, pv, dc; + struct pxa_pwm_chip *pxa_pwm = to_pxa_pwm_chip(chip); + + c = pxa_get_pwmclk(); + c = c * period_ns; + do_div(c, 1000000000); + period_cycles = c; + + if (period_cycles < 1) + period_cycles = 1; + prescale = (period_cycles - 1) / 1024; + pv = period_cycles / (prescale + 1) - 1; + + if (prescale > 63) + return -EINVAL; + + if (duty_ns == period_ns) + dc = PWMDCR_FD; + else + dc = (pv + 1) * duty_ns / period_ns; + + pxa_pwm->duty_ns = duty_ns; + pxa_pwm->period_ns = period_ns; + + /* NOTE: the clock to PWM has to be enabled first + * before writing to the registers + */ + __raw_writel(prescale, pxa_pwm->iobase + PWMCR); + __raw_writel(dc, pxa_pwm->iobase + PWMDCR); + __raw_writel(pv, pxa_pwm->iobase + PWMPCR); + + return 0; +} + +static int pxa_pwm_enable(struct pwm_chip *chip) +{ + struct pxa_pwm_chip *pxa_pwm = to_pxa_pwm_chip(chip); + + switch (pxa_pwm->id) { + case 0: + case 2: + CKEN |= CKEN_PWM0; + break; + case 1: + case 3: + CKEN |= CKEN_PWM1; + break; + default: + return -EINVAL; + } + return 0; +} + +static void pxa_pwm_disable(struct pwm_chip *chip) +{ + struct pxa_pwm_chip *pxa_pwm = to_pxa_pwm_chip(chip); + + switch (pxa_pwm->id) { + case 0: + case 2: + CKEN &= ~CKEN_PWM0; + break; + case 1: + case 3: + CKEN &= ~CKEN_PWM1; + break; + default: + break; + } +} + +static struct pwm_ops pxa_pwm_ops = { + .config = pxa_pwm_config, + .enable = pxa_pwm_enable, + .disable = pxa_pwm_disable, +}; + +static int pxa_pwm_probe(struct device_d *dev) +{ + struct pxa_pwm_chip *chip; + + chip = xzalloc(sizeof(*chip)); + chip->chip.devname = asprintf("%s", dev_name(dev)); + chip->chip.ops = &pxa_pwm_ops; + chip->iobase = dev_request_mem_region(dev, 0); + chip->id = dev->id; + dev->priv = chip; + + return pwmchip_add(&chip->chip, dev); +} + +static struct driver_d pxa_pwm_driver = { + .name = "pxa_pwm", + .probe = pxa_pwm_probe, +}; + +static int __init pxa_pwm_init_driver(void) +{ + CKEN &= ~CKEN_PWM0 & ~CKEN_PWM1; + register_driver(&pxa_pwm_driver); + return 0; +} + +device_initcall(pxa_pwm_init_driver); |