The FTM PWM device can be found on Vybrid VF610 Tower and Layerscape LS-1 SoCs. Signed-off-by: Xiubo Li <Li.Xiubo@xxxxxxxxxxxxx> Signed-off-by: Alison Wang <b18965@xxxxxxxxxxxxx> Signed-off-by: Jingchang Lu <b35083@xxxxxxxxxxxxx> Reviewed-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> --- Hi Thierry, Bill In this patch series only this one has been changed. I'm sending this patch for your comments. This patch series is the Freescale FTM PWM implementation. And there are 8 channels most supported by the FTM PWM. This implementation is only compatible with device tree definition. This patch series is based on linux-next and has been tested on Vybrid VF610 Tower board using device tree. Changes in v8 RFC: - Remove ftm_readl/ftm_writel. - Add pwm-fsl-ftm.h file. Changes in v8: - Fix some issues pointed by Thierry. - Fix the _readl/_writel of sparse check. Changes in v7: - Add big-endian mode support. - Add FTM mutex lock. - Add period time check with the current running pwm(s). - Recode the counter clock source selecting. - Sort some header files alphabetically, etc. [snip] v1~v6 drivers/pwm/Kconfig | 10 ++ drivers/pwm/Makefile | 1 + drivers/pwm/pwm-fsl-ftm.c | 426 ++++++++++++++++++++++++++++++++++++++++++++++ drivers/pwm/pwm-fsl-ftm.h | 101 +++++++++++ 4 files changed, 538 insertions(+) create mode 100644 drivers/pwm/pwm-fsl-ftm.c create mode 100644 drivers/pwm/pwm-fsl-ftm.h diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 3f66427..ec4bf78 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -71,6 +71,16 @@ config PWM_EP93XX To compile this driver as a module, choose M here: the module will be called pwm-ep93xx. +config PWM_FSL_FTM + tristate "Freescale FlexTimer Module (FTM) PWM support" + depends on OF + help + Generic FTM PWM framework driver for Freescale VF610 and + Layerscape LS-1 SoCs. + + To compile this driver as a module, choose M here: the module + will be called pwm-fsl-ftm. + config PWM_IMX tristate "i.MX PWM support" depends on ARCH_MXC diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index 8b754e4..b335db1 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -4,6 +4,7 @@ obj-$(CONFIG_PWM_AB8500) += pwm-ab8500.o obj-$(CONFIG_PWM_ATMEL_TCB) += pwm-atmel-tcb.o obj-$(CONFIG_PWM_BFIN) += pwm-bfin.o obj-$(CONFIG_PWM_EP93XX) += pwm-ep93xx.o +obj-$(CONFIG_PWM_FSL_FTM) += pwm-fsl-ftm.o obj-$(CONFIG_PWM_IMX) += pwm-imx.o obj-$(CONFIG_PWM_JZ4740) += pwm-jz4740.o obj-$(CONFIG_PWM_LPC32XX) += pwm-lpc32xx.o diff --git a/drivers/pwm/pwm-fsl-ftm.c b/drivers/pwm/pwm-fsl-ftm.c new file mode 100644 index 0000000..39093e5 --- /dev/null +++ b/drivers/pwm/pwm-fsl-ftm.c @@ -0,0 +1,426 @@ +/* + * Freescale FlexTimer Module (FTM) PWM Driver + * + * Copyright 2012-2013 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. + */ + +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/pwm.h> +#include <linux/slab.h> + +#include "pwm-fsl-ftm.h" + +static inline struct fsl_pwm_chip *to_fsl_chip(struct pwm_chip *chip) +{ + return container_of(chip, struct fsl_pwm_chip, chip); +} + +static int fsl_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct fsl_pwm_chip *fpc = to_fsl_chip(chip); + + return clk_prepare_enable(fpc->sys_clk); +} + +static void fsl_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct fsl_pwm_chip *fpc = to_fsl_chip(chip); + + clk_disable_unprepare(fpc->sys_clk); +} + +static inline int fsl_pwm_calculate_default_ps(struct fsl_pwm_chip *fpc, + enum fsl_pwm_clk index) +{ + unsigned long sys_rate, cnt_rate; + unsigned long long ratio; + + sys_rate = clk_get_rate(fpc->sys_clk); + if (!sys_rate) + return -EINVAL; + + cnt_rate = clk_get_rate(fpc->counter_clk); + if (!cnt_rate) + return -EINVAL; + + switch (index) { + case FSL_PWM_CLK_SYS: + fpc->clk_ps = 1; + break; + case FSL_PWM_CLK_FIX: + ratio = 2 * cnt_rate - 1; + do_div(ratio, sys_rate); + fpc->clk_ps = ratio; + break; + case FSL_PWM_CLK_EXT: + ratio = 4 * cnt_rate - 1; + do_div(ratio, sys_rate); + fpc->clk_ps = ratio; + break; + } + + return 0; +} + +static inline unsigned long fsl_pwm_calculate_cycles(struct fsl_pwm_chip *fpc, + unsigned long period_ns) +{ + unsigned long long c, c0; + + c = clk_get_rate(fpc->counter_clk); + c = c * period_ns; + do_div(c, 1000000000UL); + + do { + c0 = c; + do_div(c0, (1 << fpc->clk_ps)); + if (c0 <= 0xFFFF) + return (unsigned long)c0; + } while (++fpc->clk_ps < 8); + + return 0; +} + +static unsigned long fsl_pwm_calculate_period_cycles(struct fsl_pwm_chip *fpc, + unsigned long period_ns, + enum fsl_pwm_clk index) +{ + bool bg = fpc->big_endian; + int ret; + + fpc->counter_clk_select = FTM_SC_CLK(bg, index); + + ret = fsl_pwm_calculate_default_ps(fpc, index); + if (ret) { + dev_err(fpc->chip.dev, "failed to calculate default " + "prescaler: %d\n", ret); + return 0; + } + + return fsl_pwm_calculate_cycles(fpc, period_ns); +} + +static unsigned long fsl_pwm_calculate_period(struct fsl_pwm_chip *fpc, + unsigned long period_ns) +{ + struct clk *cnt_clk[3]; + enum fsl_pwm_clk m0, m1; + unsigned long fix_rate, ext_rate, cycles; + + fpc->counter_clk = fpc->sys_clk; + cycles = fsl_pwm_calculate_period_cycles(fpc, period_ns, + FSL_PWM_CLK_SYS); + if (cycles) + return cycles; + + cnt_clk[FSL_PWM_CLK_FIX] = devm_clk_get(fpc->chip.dev, "ftm_fix"); + if (IS_ERR(cnt_clk[FSL_PWM_CLK_FIX])) + return PTR_ERR(cnt_clk[FSL_PWM_CLK_FIX]); + + cnt_clk[FSL_PWM_CLK_EXT] = devm_clk_get(fpc->chip.dev, "ftm_ext"); + if (IS_ERR(cnt_clk[FSL_PWM_CLK_EXT])) + return PTR_ERR(cnt_clk[FSL_PWM_CLK_EXT]); + + fpc->counter_clk_en = devm_clk_get(fpc->chip.dev, "ftm_cnt_clk_en"); + if (IS_ERR(fpc->counter_clk_en)) + return PTR_ERR(fpc->counter_clk_en); + + fix_rate = clk_get_rate(cnt_clk[FSL_PWM_CLK_FIX]); + ext_rate = clk_get_rate(cnt_clk[FSL_PWM_CLK_EXT]); + + if (fix_rate > ext_rate) { + m0 = FSL_PWM_CLK_FIX; + m1 = FSL_PWM_CLK_EXT; + } else { + m0 = FSL_PWM_CLK_EXT; + m1 = FSL_PWM_CLK_FIX; + } + + fpc->counter_clk = cnt_clk[m0]; + cycles = fsl_pwm_calculate_period_cycles(fpc, period_ns, m0); + if (cycles) + return cycles; + + fpc->counter_clk = cnt_clk[m1]; + + return fsl_pwm_calculate_period_cycles(fpc, period_ns, m0); +} + +static unsigned long fsl_pwm_calculate_duty(struct fsl_pwm_chip *fpc, + unsigned long period_ns, + unsigned long duty_ns) +{ + unsigned long long val, duty; + + val = readl(fpc->base + FTM_MOD); + duty = duty_ns * (val + 1); + do_div(duty, period_ns); + + return (unsigned long)duty; +} + +static int fsl_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, + int duty_ns, int period_ns) +{ + struct fsl_pwm_chip *fpc = to_fsl_chip(chip); + bool bg = fpc->big_endian; + u32 val, period, duty; + + mutex_lock(&fpc->lock); + + /* + * The Freescale FTM controller supports only a single period for + * all PWM channels, therefore incompatible changes need to be + * refused. + */ + if (fpc->period_ns && fpc->period_ns != period_ns) { + dev_err(fpc->chip.dev, + "conflicting period requested for PWM %u\n", + pwm->hwpwm); + mutex_unlock(&fpc->lock); + return -EBUSY; + } + + if (!fpc->period_ns && duty_ns) { + period = fsl_pwm_calculate_period(fpc, period_ns); + if (!period) { + dev_err(fpc->chip.dev, "failed to calculate period\n"); + mutex_unlock(&fpc->lock); + return -EINVAL; + } + + val = readl(fpc->base + FTM_SC); + val &= ~FTM_SC_PS_MASK(bg); + val |= fpc->clk_ps << FTM_SC_PS_SHIFT(bg); + writel(val, fpc->base + FTM_SC); + writel(FTM_SWAP32(bg, period - 1), fpc->base + FTM_MOD); + + fpc->period_ns = period_ns; + } + + mutex_unlock(&fpc->lock); + + duty = fsl_pwm_calculate_duty(fpc, period_ns, duty_ns); + + writel((FTM_CSC_MSB(bg) | FTM_CSC_ELSB(bg)), + fpc->base + FTM_CSC(pwm->hwpwm)); + writel(FTM_SWAP32(bg, duty), fpc->base + FTM_CV(pwm->hwpwm)); + + return 0; +} + +static int fsl_pwm_set_polarity(struct pwm_chip *chip, + struct pwm_device *pwm, + enum pwm_polarity polarity) +{ + struct fsl_pwm_chip *fpc = to_fsl_chip(chip); + bool bg = fpc->big_endian; + u32 val; + + val = readl(fpc->base + FTM_POL); + + if (polarity == PWM_POLARITY_INVERSED) + val |= FTM_POL_CHAN(bg, pwm->hwpwm); + else + val &= ~FTM_POL_CHAN(bg, pwm->hwpwm); + + writel(val, fpc->base + FTM_POL); + + return 0; +} + +static int fsl_counter_clock_enable(struct fsl_pwm_chip *fpc) +{ + bool bg = fpc->big_endian; + u32 val; + int ret; + + if (fpc->counter_clk_enable++) + return 0; + + ret = clk_prepare_enable(fpc->counter_clk); + if (ret) { + fpc->counter_clk_enable--; + return ret; + } + + ret = clk_prepare_enable(fpc->counter_clk_en); + if (ret) { + fpc->counter_clk_enable--; + return ret; + } + + /* select counter clock source */ + val = readl(fpc->base + FTM_SC); + val &= ~FTM_SC_CLK_MASK(bg); + val |= fpc->counter_clk_select; + writel(val, fpc->base + FTM_SC); + + return 0; +} + +static int fsl_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct fsl_pwm_chip *fpc = to_fsl_chip(chip); + bool bg = fpc->big_endian; + u32 val; + int ret; + + val = readl(fpc->base + FTM_OUTMASK); + val &= ~FTM_OUTMASK_CHAN(bg, pwm->hwpwm); + writel(val, fpc->base + FTM_OUTMASK); + + mutex_lock(&fpc->lock); + ret = fsl_counter_clock_enable(fpc); + mutex_unlock(&fpc->lock); + + return ret; +} + +static inline void fsl_counter_clock_disable(struct fsl_pwm_chip *fpc) +{ + bool bg = fpc->big_endian; + u32 val; + + if (--fpc->counter_clk_enable) + return; + + val = readl(fpc->base + FTM_SC); + val &= ~FTM_SC_CLK_MASK(bg); + writel(val, fpc->base + FTM_SC); + + clk_disable_unprepare(fpc->counter_clk_en); + clk_disable_unprepare(fpc->counter_clk); +} + +static void fsl_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct fsl_pwm_chip *fpc = to_fsl_chip(chip); + bool bg = fpc->big_endian; + u32 val; + + val = readl(fpc->base + FTM_OUTMASK); + val |= FTM_OUTMASK_CHAN(bg, pwm->hwpwm); + writel(val, fpc->base + FTM_OUTMASK); + + mutex_lock(&fpc->lock); + + fsl_counter_clock_disable(fpc); + + val = readl(fpc->base + FTM_OUTMASK); + + if ((val & FTM_OUTMASK_CHAN_MASK(bg)) == FTM_OUTMASK_CHAN_MASK(bg)) { + fpc->period_ns = 0; + fpc->counter_clk_en = NULL; + } + + mutex_unlock(&fpc->lock); +} + +static const struct pwm_ops fsl_pwm_ops = { + .request = fsl_pwm_request, + .free = fsl_pwm_free, + .config = fsl_pwm_config, + .set_polarity = fsl_pwm_set_polarity, + .enable = fsl_pwm_enable, + .disable = fsl_pwm_disable, + .owner = THIS_MODULE, +}; + +static int fsl_pwm_probe(struct platform_device *pdev) +{ + struct fsl_pwm_chip *fpc; + struct resource *res; + struct device_node *np = pdev->dev.of_node; + int ret; + + fpc = devm_kzalloc(&pdev->dev, sizeof(*fpc), GFP_KERNEL); + if (!fpc) + return -ENOMEM; + + mutex_init(&fpc->lock); + + fpc->chip.dev = &pdev->dev; + + fpc->big_endian = of_property_read_bool(np, "big-endian"); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + fpc->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(fpc->base)) + return PTR_ERR(fpc->base); + + fpc->sys_clk = devm_clk_get(&pdev->dev, "ftm_sys"); + if (IS_ERR(fpc->sys_clk)) { + dev_err(&pdev->dev, + "failed to get \"ftm_sys\" clock\n"); + return PTR_ERR(fpc->sys_clk); + } + + ret = clk_prepare_enable(fpc->sys_clk); + if (ret) + return ret; + + writel(0x0, fpc->base + FTM_CNTIN); + writel(0x0, fpc->base + FTM_OUTINIT); + writel(FTM_OUTMASK_CHAN_MASK(fpc->big_endian), + fpc->base + FTM_OUTMASK); + clk_disable_unprepare(fpc->sys_clk); + + fpc->chip.ops = &fsl_pwm_ops; + fpc->chip.of_xlate = of_pwm_xlate_with_flags; + fpc->chip.of_pwm_n_cells = 3; + fpc->chip.base = -1; + fpc->chip.npwm = 8; + + ret = pwmchip_add(&fpc->chip); + if (ret < 0) { + dev_err(&pdev->dev, "failed to add PWM chip : %d\n", ret); + return ret; + } + + platform_set_drvdata(pdev, fpc); + + return 0; +} + +static int fsl_pwm_remove(struct platform_device *pdev) +{ + struct fsl_pwm_chip *fpc = platform_get_drvdata(pdev); + + mutex_destroy(&fpc->lock); + + return pwmchip_remove(&fpc->chip); +} + +static const struct of_device_id fsl_pwm_dt_ids[] = { + { .compatible = "fsl,vf610-ftm-pwm", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, fsl_pwm_dt_ids); + +static struct platform_driver fsl_pwm_driver = { + .driver = { + .name = "fsl-ftm-pwm", + .of_match_table = fsl_pwm_dt_ids, + }, + .probe = fsl_pwm_probe, + .remove = fsl_pwm_remove, +}; +module_platform_driver(fsl_pwm_driver); + +MODULE_DESCRIPTION("Freescale FlexTimer Module PWM Driver"); +MODULE_AUTHOR("Xiubo Li <Li.Xiubo@xxxxxxxxxxxxx>"); +MODULE_ALIAS("platform:fsl-ftm-pwm"); +MODULE_LICENSE("GPL"); diff --git a/drivers/pwm/pwm-fsl-ftm.h b/drivers/pwm/pwm-fsl-ftm.h new file mode 100644 index 0000000..5fb79ae --- /dev/null +++ b/drivers/pwm/pwm-fsl-ftm.h @@ -0,0 +1,101 @@ +/* + * Copyright 2012-2013 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. + */ + +#ifndef __PWM_FSL_FTM_H +#define __PWM_FSL_FTM_H + +#include <linux/clk.h> +#include <linux/mutex.h> +#include <linux/pwm.h> + +#define FTM_SC 0x00 +#define FTM_SC_CLK_SHIFT(b) (b ? 27 : 3) +#define FTM_SC_CLK_MASK(b) (0x3 << FTM_SC_CLK_SHIFT(b)) +#define FTM_SC_CLK(b, c) ((c + 1) << FTM_SC_CLK_SHIFT(b)) +#define FTM_SC_PS_SHIFT(b) (b ? 24 : 0) +#define FTM_SC_PS_MASK(b) (0x7 << FTM_SC_PS_SHIFT(b)) + +#define FTM_CNT 0x04 +#define FTM_MOD 0x08 + +#define FTM_CSC_BASE 0x0C +#define FTM_CSC_MSB(b) (b ? BIT(29) : BIT(5)) +#define FTM_CSC_MSA(b) (b ? BIT(28) : BIT(4)) +#define FTM_CSC_ELSB(b) (b ? BIT(27) : BIT(3)) +#define FTM_CSC_ELSA(b) (b ? BIT(26) : BIT(2)) +#define FTM_CSC(_channel) (FTM_CSC_BASE + ((_channel) * 8)) + +#define FTM_CV_BASE 0x10 +#define FTM_CV(_channel) (FTM_CV_BASE + ((_channel) * 8)) + +#define FTM_CNTIN 0x4C +#define FTM_STATUS 0x50 + +#define FTM_MODE 0x54 +#define FTM_MODE_FTMEN(b) (b ? BIT(24) : BIT(0)) +#define FTM_MODE_INIT(b) (b ? BIT(26) : BIT(2)) +#define FTM_MODE_PWMSYNC(b) (b ? BIT(27) : BIT(3)) + +#define FTM_SYNC 0x58 +#define FTM_OUTINIT 0x5C + +#define FTM_OUTMASK 0x60 +#define FTM_OUTMASK_CHAN_MASK(b) (b ? 0xFF00 : 0xFF) +#define FTM_OUTMASK_CHAN(b, c) (b ? BIT(24 + c) : BIT(c)) + +#define FTM_COMBINE 0x64 +#define FTM_DEADTIME 0x68 +#define FTM_EXTTRIG 0x6C + +#define FTM_POL 0x70 +#define FTM_POL_CHAN(b, c) (b ? BIT(24 + c) : BIT(c)) + +#define FTM_FMS 0x74 +#define FTM_FILTER 0x78 +#define FTM_FLTCTRL 0x7C +#define FTM_QDCTRL 0x80 +#define FTM_CONF 0x84 +#define FTM_FLTPOL 0x88 +#define FTM_SYNCONF 0x8C +#define FTM_INVCTRL 0x90 +#define FTM_SWOCTRL 0x94 +#define FTM_PWMLOAD 0x98 + +#define __FTM_SWAP32(v) ((u32)(\ + (((u32)(v) & (u32)0x000000ffUL) << 24) |\ + (((u32)(v) & (u32)0x0000ff00UL) << 8) |\ + (((u32)(v) & (u32)0x00ff0000UL) >> 8) |\ + (((u32)(v) & (u32)0xff000000UL) >> 24))) +#define FTM_SWAP32(b, v) (b ? __FTM_SWAP32(v) : v) + +enum fsl_pwm_clk { + FSL_PWM_CLK_SYS, + FSL_PWM_CLK_FIX, + FSL_PWM_CLK_EXT, +}; + +struct fsl_pwm_chip { + struct pwm_chip chip; + + struct mutex lock; + + struct clk *sys_clk; + struct clk *counter_clk; + struct clk *counter_clk_en; + unsigned int counter_clk_select; + unsigned int counter_clk_enable; + unsigned int clk_ps; + + void __iomem *base; + + int period_ns; + bool big_endian; +}; + +#endif /* __PWM_FSL_FTM_H */ -- 1.8.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html