From mboxrd@z Thu Jan 1 00:00:00 1970 From: Donghwa Lee Date: Wed, 02 Mar 2011 10:44:42 +0900 Subject: [U-Boot] [PATCH] armv7: s5p: pwm driver support In-Reply-To: References: <1298534170-23796-1-git-send-email-dh09.lee@samsung.com> Message-ID: <4D6DA10A.6080209@samsung.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Dear Minkyu Kang, On 2011-02-28 8:36 Minkyu Kang wrote: > Dear Donghwa Lee, > > On 24 February 2011 16:56, Donghwa Lee wrote: >> This is common pwm driver of S5P. >> >> Signed-off-by: Donghwa Lee >> Signed-off-by: Kyungmin Park >> >> --- >> arch/arm/cpu/armv7/s5p-common/Makefile | 1 + >> arch/arm/cpu/armv7/s5p-common/pwm.c | 214 +++++++++++++++++++++++++++++++ >> arch/arm/include/asm/arch-s5pc1xx/pwm.h | 14 ++ >> arch/arm/include/asm/arch-s5pc2xx/pwm.h | 14 ++ >> include/pwm.h | 21 +++ >> 5 files changed, 264 insertions(+), 0 deletions(-) >> create mode 100644 arch/arm/cpu/armv7/s5p-common/pwm.c >> create mode 100644 include/pwm.h >> >> diff --git a/arch/arm/cpu/armv7/s5p-common/pwm.c b/arch/arm/cpu/armv7/s5p-common/pwm.c >> new file mode 100644 >> index 0000000..eed2206 >> --- /dev/null >> +++ b/arch/arm/cpu/armv7/s5p-common/pwm.c >> @@ -0,0 +1,214 @@ >> +/* >> + * Copyright (C) 2011 Samsung Electronics >> + * >> + * Donghwa Lee >> + * >> + * See file CREDITS for list of people who contributed to this >> + * project. >> + * >> + * 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 >> +#include >> +#include >> +#include >> +#include >> +#include >> + >> +#define PRESCALER_0 (8 - 1) /* prescaler of timer 0, 1 */ >> +#define PRESCALER_1 (16 - 1) /* prescaler of timer 2, 3, 4 */ >> +#define MUX_DIV_1 0 /* 1/1 period */ >> +#define MUX_DIV_2 1 /* 1/2 period */ >> +#define MUX_DIV_4 2 /* 1/4 period */ >> +#define MUX_DIV_8 3 /* 1/8 period */ >> +#define MUX_DIV_16 4 /* 1/16 period */ >> + >> +#define MUX_DIV_SHIFT(x) ((x) * 4) >> + >> +#define TCON0_TIMER_SHIFT 0 >> +#define TCON_TIMER_SHIFT(x) (8 + ((x - 1) * 4)) >> + >> + > please remove this space > Yes, I will remove it. >> +int pwm_enable(int pwm_id) >> +{ >> + const struct s5p_timer *pwm = (struct s5p_timer *)samsung_get_base_timer(); >> + unsigned long tcon; >> + >> + tcon = readl(&pwm->tcon); >> + >> + if (pwm_id == 0) >> + tcon |= TCON0_START; >> + else >> + tcon |= TCON_START(pwm_id); >> + writel(tcon, &pwm->tcon); >> + >> + return 0; >> +} >> + >> +void pwm_disable(int pwm_id) >> +{ >> + const struct s5p_timer *pwm = (struct s5p_timer *)samsung_get_base_timer(); >> + unsigned long tcon; >> + >> + tcon = readl(&pwm->tcon); >> + if (pwm_id == 0) >> + tcon &= ~TCON0_START; >> + else >> + tcon &= ~TCON_START(pwm_id); >> + >> + writel(tcon, &pwm->tcon); >> + > please remove this space > Yes, I will remove it. >> +} >> + >> +static unsigned long pwm_calc_tin(int pwm_id, unsigned long freq) >> +{ >> + unsigned long tin_parent_rate; >> + unsigned int div; >> + >> + tin_parent_rate = get_pwm_clk(); >> + >> + for (div = 2; div <= 16; div *= 2) { >> + if ((tin_parent_rate / (div << 16)) < freq) >> + return tin_parent_rate / div; >> + } >> + >> + return tin_parent_rate / 16; >> +} >> + >> +#define NS_IN_HZ (1000000000UL) >> + >> +int pwm_config(int pwm_id, int duty_ns, int period_ns) >> +{ >> + const struct s5p_timer *pwm = (struct s5p_timer *)samsung_get_base_timer(); >> + unsigned int offset; >> + unsigned long tin_rate; >> + unsigned long tin_ns; >> + unsigned long period; >> + unsigned long tcon; >> + unsigned long tcnt; >> + unsigned long timer_rate_hz; >> + > please remove this space > Yes, I will remove it. >> + long tcmp; > unsigned long? > Yes, I will fix it next version. >> + >> + /* We currently avoid using 64bit arithmetic by using the >> + * fact that anything faster than 1GHz is easily representable >> + * by 32bits. */ > Please keep multi-line comment rule. > Please see chapter 8. > http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=blob;f=Documentation/CodingStyle > Thank you, your comment. I will fix it. >> + if (period_ns > NS_IN_HZ || duty_ns > NS_IN_HZ) >> + return -ERANGE; >> + >> + if (duty_ns > period_ns) >> + return -EINVAL; >> + >> + period = NS_IN_HZ / period_ns; >> + >> + /* Check to see if we are changing the clock rate of the PWM */ >> + tin_rate = pwm_calc_tin(pwm_id, period); >> + timer_rate_hz = tin_rate; >> + >> + tin_ns = NS_IN_HZ / tin_rate; >> + tcnt = period_ns / tin_ns; >> + >> + /* Note, counters count down */ >> + tcmp = duty_ns / tin_ns; >> + tcmp = tcnt - tcmp; >> + >> + /* the pwm hw only checks the compare register after a decrement, >> + so the pin never toggles if tcmp = tcnt */ >> + if (tcmp == tcnt) >> + tcmp--; >> + >> + if (tcmp < 0) >> + tcmp = 0; >> + >> + /* Update the PWM register block. */ >> + writel(tcmp, &pwm->tcmpb0 + offset); > offset is not initialized. > And, timer4 doesn't have tcmpb register. > Please check pwm_id. > offset variable was missed. I will add it next version and fix about timer 4. >> + writel(tcnt, &pwm->tcntb0 + offset); >> + >> + tcon = readl(&pwm->tcon); >> + if (pwm_id == 0) { >> + tcon |= TCON0_UPDATE; >> + tcon |= TCON0_AUTO_RELOAD; >> + } else { >> + tcon |= TCON_UPDATE(pwm_id); >> + tcon |= TCON_AUTO_RELOAD(pwm_id); >> + } >> + >> + writel(tcon, &pwm->tcon); >> + >> + if (pwm_id == 0) >> + tcon &= ~TCON0_UPDATE; >> + else >> + tcon &= ~TCON_UPDATE(pwm_id); >> + >> + writel(tcon, &pwm->tcon); >> + >> + return 0; >> +} >> + >> +int pwm_init(int pwm_id, int div, int invert) >> +{ >> + u32 val; >> + const struct s5p_timer *pwm = (struct s5p_timer *)samsung_get_base_timer(); >> + unsigned long timer_rate_hz; >> + unsigned int offset, prescaler; >> + >> + /* >> + * @ PWM Timer 0 > Timer 0 is right? > >> + * Timer Freq(HZ) = >> + * PWM_CLK / { (prescaler_value + 1) * (divider_value) } >> + */ >> + >> + val = readl(&pwm->tcfg0); >> + if (pwm_id < 2) { >> + prescaler = PRESCALER_0; >> + val &= ~0xff; >> + val |= (prescaler & 0xff); >> + } else { >> + prescaler = PRESCALER_1; >> + val &= ~(0xff << 8); >> + val |= (prescaler & 0xff) << 8; >> + } >> + writel(val, &pwm->tcfg0); >> + val = readl(&pwm->tcfg1); >> + val &= ~(0xf << MUX_DIV_SHIFT(pwm_id)); >> + val |= (div & 0xf) << MUX_DIV_SHIFT(pwm_id); >> + writel(val, &pwm->tcfg1); >> + >> + timer_rate_hz = get_pwm_clk() / ((prescaler + 1) * >> + (div + 1)); >> + >> + timer_rate_hz = timer_rate_hz / 100; >> + >> + /* set count value */ >> + offset = pwm_id * 0xc; >> + writel(timer_rate_hz, &pwm->tcntb0 + offset); >> + >> + if (pwm_id == 0) { >> + val = readl(&pwm->tcon) & ~(0xf << TCON0_TIMER_SHIFT); >> + if (invert) >> + val |= TCON0_INVERTER; >> + } else { >> + val = readl(&pwm->tcon) & ~(0xf << TCON_TIMER_SHIFT(pwm_id)); >> + if (invert) >> + val |= TCON_INVERT(pwm_id); > TCON0_INVERTER and TCON_INVERT().. > inverter or invert? > Please use same name. > Maybe I think INVERTER is right, I will fix it. >> + } >> + >> + writel(val, &pwm->tcon); > Pleas use tap instead of space. > >> + pwm_enable(pwm_id); >> + >> + return 0; >> +} >> diff --git a/include/pwm.h b/include/pwm.h >> new file mode 100644 >> index 0000000..b09a02f >> --- /dev/null >> +++ b/include/pwm.h >> @@ -0,0 +1,21 @@ >> +/* >> + * header file for pwm driver. >> + * >> + * copyright (c) 2011 samsung electronics >> + * donghwa lee >> + * >> + * 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. > Please write full license. > Yes, I will add full license. > Thanks > Minkyu Kang Thank you, Donghwa Lee