diff options
-rw-r--r-- | drivers/misc/Makefile | 1 | ||||
-rw-r--r-- | drivers/misc/imx_pwm.c | 120 | ||||
-rw-r--r-- | include/asm-arm/imx_pwm.h | 37 |
3 files changed, 158 insertions, 0 deletions
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index 448b9cb..5bbafea 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -29,6 +29,7 @@ COBJS-$(CONFIG_ALI152X) += ali512x.o COBJS-$(CONFIG_DS4510) += ds4510.o COBJS-$(CONFIG_FSL_LAW) += fsl_law.o COBJS-$(CONFIG_IMX_IIM) += imx_iim.o +COBJS-$(CONFIG_IMX_PWM) += imx_pwm.o COBJS-$(CONFIG_NS87308) += ns87308.o COBJS-$(CONFIG_STATUS_LED) += status_led.o COBJS-$(CONFIG_TWL4030_LED) += twl4030_led.o diff --git a/drivers/misc/imx_pwm.c b/drivers/misc/imx_pwm.c new file mode 100644 index 0000000..97c7df0 --- /dev/null +++ b/drivers/misc/imx_pwm.c @@ -0,0 +1,120 @@ +/* + * Porting to u-boot: + * Linux IMX PWM driver + * + * Copyright (C) 2011 Freescale Semiconductor, Inc. + * + * 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., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <linux/types.h> +#include <asm/io.h> +#include <asm/imx_pwm.h> +#include <common.h> +#include <div64.h> + +#define MX_PWMCR 0x00 /* PWM Control Register */ +#define MX_PWMSAR 0x0C /* PWM Sample Register */ +#define MX_PWMPR 0x10 /* PWM Period Register */ +#define MX_PWMCR_PRESCALER(x) (((x - 1) & 0xFFF) << 4) +#define MX_PWMCR_CLKSRC_IPG_HIGH (2 << 16) +#define MX_PWMCR_CLKSRC_IPG (1 << 16) +#define MX_PWMCR_EN (1 << 0) + +#define MX_PWMCR_STOPEN (1 << 25) +#define MX_PWMCR_DOZEEN (1 << 24) +#define MX_PWMCR_WAITEN (1 << 23) +#define MX_PWMCR_DBGEN (1 << 22) +#define MX_PWMCR_CLKSRC_IPG (1 << 16) +#define MX_PWMCR_CLKSRC_IPG_32k (3 << 16) + +int imx_pwm_config(struct pwm_device pwm, int duty_ns, int period_ns) +{ + unsigned long long c; + unsigned long period_cycles, duty_cycles, prescale; + u32 cr; + + if (period_ns == 0 || duty_ns > period_ns) + return -1; + + pwm.mmio_base = pwm.pwm_id ? (unsigned long)IMX_PWM2_BASE: + (unsigned long)IMX_PWM1_BASE; + + if (pwm.pwmo_invert) + duty_ns = period_ns - duty_ns; + + c = mxc_get_clock(MXC_IPG_PERCLK); + c = c * period_ns; + do_div(c, 1000000000); + period_cycles = c; + + prescale = period_cycles / 0x10000 + 1; + + period_cycles /= prescale; + c = (unsigned long long)period_cycles * duty_ns; + do_div(c, period_ns); + duty_cycles = c; + + writel(duty_cycles, pwm.mmio_base + MX_PWMSAR); + writel(period_cycles, pwm.mmio_base + MX_PWMPR); + + cr = MX_PWMCR_PRESCALER(prescale) | + MX_PWMCR_STOPEN | MX_PWMCR_DOZEEN | + MX_PWMCR_WAITEN | MX_PWMCR_DBGEN; + + cr |= MX_PWMCR_CLKSRC_IPG_HIGH; + + writel(cr, pwm.mmio_base + MX_PWMCR); + + return 0; +} + +int imx_pwm_enable(struct pwm_device pwm) +{ + unsigned long reg; + int rc = 0; + + if (pwm.enable_pwm_clk) + pwm.enable_pwm_clk(); + + pwm.mmio_base = pwm.pwm_id ? (unsigned long)IMX_PWM2_BASE: + (unsigned long)IMX_PWM1_BASE; + + reg = readl(pwm.mmio_base + MX_PWMCR); + reg |= MX_PWMCR_EN; + writel(reg, pwm.mmio_base + MX_PWMCR); + + if (pwm.enable_pwm_pad) + pwm.enable_pwm_pad(); + + return rc; +} + +int imx_pwm_disable(struct pwm_device pwm) +{ + if (pwm.disable_pwm_pad) + pwm.disable_pwm_pad(); + + pwm.mmio_base = pwm.pwm_id ? (unsigned long)IMX_PWM2_BASE: + (unsigned long)IMX_PWM1_BASE; + + writel(0, pwm.mmio_base + MX_PWMCR); + + if (pwm.disable_pwm_clk) + pwm.disable_pwm_clk(); + + return 0; +} diff --git a/include/asm-arm/imx_pwm.h b/include/asm-arm/imx_pwm.h new file mode 100644 index 0000000..2e4a52a --- /dev/null +++ b/include/asm-arm/imx_pwm.h @@ -0,0 +1,37 @@ +/* + * Copyright (C) 2011 Freescale Semiconductor, Inc. + * + * 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., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#ifndef __IMX_PWM_H__ +#define __IMX_PWM_H__ + +struct pwm_device { + unsigned long mmio_base; + unsigned int pwm_id; + int pwmo_invert; + void (*enable_pwm_pad)(void); + void (*disable_pwm_pad)(void); + void (*enable_pwm_clk)(void); + void (*disable_pwm_clk)(void); +}; + +int imx_pwm_config(struct pwm_device pwm, int duty_ns, int period_ns); +int imx_pwm_enable(struct pwm_device pwm); +int imx_pwm_disable(struct pwm_device pwm); + +#endif |