Commit 9a8b2aa5 authored by Linus Torvalds's avatar Linus Torvalds

Merge tag 'pwm/for-3.20-rc1' of...

Merge tag 'pwm/for-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
 "This contains two new drivers, one for Allwinner SoCs and the other
  for Imagination Technologies' Pistachio SoC.

  Complementing this are a couple of fixes to the Atmel HLCDC PWM and
  STi PWM drivers as well as minor cleanups to the core and the Tegra
  driver"

* tag 'pwm/for-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm:
  pwm: tegra: Use NSEC_PER_SEC
  pwm: Remove unnecessary check before of_node_put()
  pwm: Add device tree binding document for IMG PWM DAC
  pwm: Imagination Technologies PWM DAC driver
  pwm: sti: Maintain a bitmap of configured devices
  pwm: sunxi: document OF bindings
  pwm: Add Allwinner SoC support
  pwm: atmel-hlcdc: Prevent division by zero
  pwm: atmel-hlcdc: Depend on HAVE_CLK
parents ce1d3fde b65af27a
*Imagination Technologies PWM DAC driver
Required properties:
- compatible: Should be "img,pistachio-pwm"
- reg: Should contain physical base address and length of pwm registers.
- clocks: Must contain an entry for each entry in clock-names.
See ../clock/clock-bindings.txt for details.
- clock-names: Must include the following entries.
- pwm: PWM operating clock.
- sys: PWM system interface clock.
- #pwm-cells: Should be 2. See pwm.txt in this directory for the
description of the cells format.
- img,cr-periph: Must contain a phandle to the peripheral control
syscon node which contains PWM control registers.
Example:
pwm: pwm@18101300 {
compatible = "img,pistachio-pwm";
reg = <0x18101300 0x100>;
clocks = <&pwm_clk>, <&system_clk>;
clock-names = "pwm", "sys";
#pwm-cells = <2>;
img,cr-periph = <&cr_periph>;
};
Allwinner sun4i and sun7i SoC PWM controller
Required properties:
- compatible: should be one of:
- "allwinner,sun4i-a10-pwm"
- "allwinner,sun7i-a20-pwm"
- reg: physical base address and length of the controller's registers
- #pwm-cells: should be 3. See pwm.txt in this directory for a description of
the cells format.
- clocks: From common clock binding, handle to the parent clock.
Example:
pwm: pwm@01c20e00 {
compatible = "allwinner,sun7i-a20-pwm";
reg = <0x01c20e00 0xc>;
clocks = <&osc24M>;
#pwm-cells = <3>;
status = "disabled";
};
...@@ -53,6 +53,7 @@ config PWM_ATMEL ...@@ -53,6 +53,7 @@ config PWM_ATMEL
config PWM_ATMEL_HLCDC_PWM config PWM_ATMEL_HLCDC_PWM
tristate "Atmel HLCDC PWM support" tristate "Atmel HLCDC PWM support"
depends on MFD_ATMEL_HLCDC depends on MFD_ATMEL_HLCDC
depends on HAVE_CLK
help help
Generic PWM framework driver for the PWM output of the HLCDC Generic PWM framework driver for the PWM output of the HLCDC
(Atmel High-end LCD Controller). This PWM output is mainly used (Atmel High-end LCD Controller). This PWM output is mainly used
...@@ -130,6 +131,19 @@ config PWM_FSL_FTM ...@@ -130,6 +131,19 @@ config PWM_FSL_FTM
To compile this driver as a module, choose M here: the module To compile this driver as a module, choose M here: the module
will be called pwm-fsl-ftm. will be called pwm-fsl-ftm.
config PWM_IMG
tristate "Imagination Technologies PWM driver"
depends on HAS_IOMEM
depends on MFD_SYSCON
depends on COMMON_CLK
depends on MIPS || COMPILE_TEST
help
Generic PWM framework driver for Imagination Technologies
PWM block which supports 4 channels.
To compile this driver as a module, choose M here: the module
will be called pwm-img
config PWM_IMX config PWM_IMX
tristate "i.MX PWM support" tristate "i.MX PWM support"
depends on ARCH_MXC depends on ARCH_MXC
...@@ -283,6 +297,16 @@ config PWM_STI ...@@ -283,6 +297,16 @@ config PWM_STI
To compile this driver as a module, choose M here: the module To compile this driver as a module, choose M here: the module
will be called pwm-sti. will be called pwm-sti.
config PWM_SUN4I
tristate "Allwinner PWM support"
depends on ARCH_SUNXI || COMPILE_TEST
depends on HAS_IOMEM && COMMON_CLK
help
Generic PWM framework driver for Allwinner SoCs.
To compile this driver as a module, choose M here: the module
will be called pwm-sun4i.
config PWM_TEGRA config PWM_TEGRA
tristate "NVIDIA Tegra PWM support" tristate "NVIDIA Tegra PWM support"
depends on ARCH_TEGRA depends on ARCH_TEGRA
......
...@@ -10,6 +10,7 @@ obj-$(CONFIG_PWM_BFIN) += pwm-bfin.o ...@@ -10,6 +10,7 @@ obj-$(CONFIG_PWM_BFIN) += pwm-bfin.o
obj-$(CONFIG_PWM_CLPS711X) += pwm-clps711x.o obj-$(CONFIG_PWM_CLPS711X) += pwm-clps711x.o
obj-$(CONFIG_PWM_EP93XX) += pwm-ep93xx.o obj-$(CONFIG_PWM_EP93XX) += pwm-ep93xx.o
obj-$(CONFIG_PWM_FSL_FTM) += pwm-fsl-ftm.o obj-$(CONFIG_PWM_FSL_FTM) += pwm-fsl-ftm.o
obj-$(CONFIG_PWM_IMG) += pwm-img.o
obj-$(CONFIG_PWM_IMX) += pwm-imx.o obj-$(CONFIG_PWM_IMX) += pwm-imx.o
obj-$(CONFIG_PWM_JZ4740) += pwm-jz4740.o obj-$(CONFIG_PWM_JZ4740) += pwm-jz4740.o
obj-$(CONFIG_PWM_LP3943) += pwm-lp3943.o obj-$(CONFIG_PWM_LP3943) += pwm-lp3943.o
...@@ -26,6 +27,7 @@ obj-$(CONFIG_PWM_ROCKCHIP) += pwm-rockchip.o ...@@ -26,6 +27,7 @@ obj-$(CONFIG_PWM_ROCKCHIP) += pwm-rockchip.o
obj-$(CONFIG_PWM_SAMSUNG) += pwm-samsung.o obj-$(CONFIG_PWM_SAMSUNG) += pwm-samsung.o
obj-$(CONFIG_PWM_SPEAR) += pwm-spear.o obj-$(CONFIG_PWM_SPEAR) += pwm-spear.o
obj-$(CONFIG_PWM_STI) += pwm-sti.o obj-$(CONFIG_PWM_STI) += pwm-sti.o
obj-$(CONFIG_PWM_SUN4I) += pwm-sun4i.o
obj-$(CONFIG_PWM_TEGRA) += pwm-tegra.o obj-$(CONFIG_PWM_TEGRA) += pwm-tegra.o
obj-$(CONFIG_PWM_TIECAP) += pwm-tiecap.o obj-$(CONFIG_PWM_TIECAP) += pwm-tiecap.o
obj-$(CONFIG_PWM_TIEHRPWM) += pwm-tiehrpwm.o obj-$(CONFIG_PWM_TIEHRPWM) += pwm-tiehrpwm.o
......
...@@ -192,7 +192,7 @@ static void of_pwmchip_add(struct pwm_chip *chip) ...@@ -192,7 +192,7 @@ static void of_pwmchip_add(struct pwm_chip *chip)
static void of_pwmchip_remove(struct pwm_chip *chip) static void of_pwmchip_remove(struct pwm_chip *chip)
{ {
if (chip->dev && chip->dev->of_node) if (chip->dev)
of_node_put(chip->dev->of_node); of_node_put(chip->dev->of_node);
} }
......
...@@ -64,6 +64,9 @@ static int atmel_hlcdc_pwm_config(struct pwm_chip *c, ...@@ -64,6 +64,9 @@ static int atmel_hlcdc_pwm_config(struct pwm_chip *c,
if (!chip->errata || !chip->errata->slow_clk_erratum) { if (!chip->errata || !chip->errata->slow_clk_erratum) {
clk_freq = clk_get_rate(new_clk); clk_freq = clk_get_rate(new_clk);
if (!clk_freq)
return -EINVAL;
clk_period_ns = (u64)NSEC_PER_SEC * 256; clk_period_ns = (u64)NSEC_PER_SEC * 256;
do_div(clk_period_ns, clk_freq); do_div(clk_period_ns, clk_freq);
} }
...@@ -73,6 +76,9 @@ static int atmel_hlcdc_pwm_config(struct pwm_chip *c, ...@@ -73,6 +76,9 @@ static int atmel_hlcdc_pwm_config(struct pwm_chip *c,
clk_period_ns > period_ns) { clk_period_ns > period_ns) {
new_clk = hlcdc->sys_clk; new_clk = hlcdc->sys_clk;
clk_freq = clk_get_rate(new_clk); clk_freq = clk_get_rate(new_clk);
if (!clk_freq)
return -EINVAL;
clk_period_ns = (u64)NSEC_PER_SEC * 256; clk_period_ns = (u64)NSEC_PER_SEC * 256;
do_div(clk_period_ns, clk_freq); do_div(clk_period_ns, clk_freq);
} }
......
/*
* Imagination Technologies Pulse Width Modulator driver
*
* Copyright (c) 2014-2015, Imagination Technologies
*
* Based on drivers/pwm/pwm-tegra.c, Copyright (c) 2010, NVIDIA Corporation
*
* 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.
*/
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pwm.h>
#include <linux/regmap.h>
#include <linux/slab.h>
/* PWM registers */
#define PWM_CTRL_CFG 0x0000
#define PWM_CTRL_CFG_NO_SUB_DIV 0
#define PWM_CTRL_CFG_SUB_DIV0 1
#define PWM_CTRL_CFG_SUB_DIV1 2
#define PWM_CTRL_CFG_SUB_DIV0_DIV1 3
#define PWM_CTRL_CFG_DIV_SHIFT(ch) ((ch) * 2 + 4)
#define PWM_CTRL_CFG_DIV_MASK 0x3
#define PWM_CH_CFG(ch) (0x4 + (ch) * 4)
#define PWM_CH_CFG_TMBASE_SHIFT 0
#define PWM_CH_CFG_DUTY_SHIFT 16
#define PERIP_PWM_PDM_CONTROL 0x0140
#define PERIP_PWM_PDM_CONTROL_CH_MASK 0x1
#define PERIP_PWM_PDM_CONTROL_CH_SHIFT(ch) ((ch) * 4)
#define MAX_TMBASE_STEPS 65536
struct img_pwm_chip {
struct device *dev;
struct pwm_chip chip;
struct clk *pwm_clk;
struct clk *sys_clk;
void __iomem *base;
struct regmap *periph_regs;
};
static inline struct img_pwm_chip *to_img_pwm_chip(struct pwm_chip *chip)
{
return container_of(chip, struct img_pwm_chip, chip);
}
static inline void img_pwm_writel(struct img_pwm_chip *chip,
u32 reg, u32 val)
{
writel(val, chip->base + reg);
}
static inline u32 img_pwm_readl(struct img_pwm_chip *chip,
u32 reg)
{
return readl(chip->base + reg);
}
static int img_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
int duty_ns, int period_ns)
{
u32 val, div, duty, timebase;
unsigned long mul, output_clk_hz, input_clk_hz;
struct img_pwm_chip *pwm_chip = to_img_pwm_chip(chip);
input_clk_hz = clk_get_rate(pwm_chip->pwm_clk);
output_clk_hz = DIV_ROUND_UP(NSEC_PER_SEC, period_ns);
mul = DIV_ROUND_UP(input_clk_hz, output_clk_hz);
if (mul <= MAX_TMBASE_STEPS) {
div = PWM_CTRL_CFG_NO_SUB_DIV;
timebase = DIV_ROUND_UP(mul, 1);
} else if (mul <= MAX_TMBASE_STEPS * 8) {
div = PWM_CTRL_CFG_SUB_DIV0;
timebase = DIV_ROUND_UP(mul, 8);
} else if (mul <= MAX_TMBASE_STEPS * 64) {
div = PWM_CTRL_CFG_SUB_DIV1;
timebase = DIV_ROUND_UP(mul, 64);
} else if (mul <= MAX_TMBASE_STEPS * 512) {
div = PWM_CTRL_CFG_SUB_DIV0_DIV1;
timebase = DIV_ROUND_UP(mul, 512);
} else if (mul > MAX_TMBASE_STEPS * 512) {
dev_err(chip->dev,
"failed to configure timebase steps/divider value\n");
return -EINVAL;
}
duty = DIV_ROUND_UP(timebase * duty_ns, period_ns);
val = img_pwm_readl(pwm_chip, PWM_CTRL_CFG);
val &= ~(PWM_CTRL_CFG_DIV_MASK << PWM_CTRL_CFG_DIV_SHIFT(pwm->hwpwm));
val |= (div & PWM_CTRL_CFG_DIV_MASK) <<
PWM_CTRL_CFG_DIV_SHIFT(pwm->hwpwm);
img_pwm_writel(pwm_chip, PWM_CTRL_CFG, val);
val = (duty << PWM_CH_CFG_DUTY_SHIFT) |
(timebase << PWM_CH_CFG_TMBASE_SHIFT);
img_pwm_writel(pwm_chip, PWM_CH_CFG(pwm->hwpwm), val);
return 0;
}
static int img_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
u32 val;
struct img_pwm_chip *pwm_chip = to_img_pwm_chip(chip);
val = img_pwm_readl(pwm_chip, PWM_CTRL_CFG);
val |= BIT(pwm->hwpwm);
img_pwm_writel(pwm_chip, PWM_CTRL_CFG, val);
regmap_update_bits(pwm_chip->periph_regs, PERIP_PWM_PDM_CONTROL,
PERIP_PWM_PDM_CONTROL_CH_MASK <<
PERIP_PWM_PDM_CONTROL_CH_SHIFT(pwm->hwpwm), 0);
return 0;
}
static void img_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
{
u32 val;
struct img_pwm_chip *pwm_chip = to_img_pwm_chip(chip);
val = img_pwm_readl(pwm_chip, PWM_CTRL_CFG);
val &= ~BIT(pwm->hwpwm);
img_pwm_writel(pwm_chip, PWM_CTRL_CFG, val);
}
static const struct pwm_ops img_pwm_ops = {
.config = img_pwm_config,
.enable = img_pwm_enable,
.disable = img_pwm_disable,
.owner = THIS_MODULE,
};
static int img_pwm_probe(struct platform_device *pdev)
{
int ret;
struct resource *res;
struct img_pwm_chip *pwm;
pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL);
if (!pwm)
return -ENOMEM;
pwm->dev = &pdev->dev;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
pwm->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(pwm->base))
return PTR_ERR(pwm->base);
pwm->periph_regs = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
"img,cr-periph");
if (IS_ERR(pwm->periph_regs))
return PTR_ERR(pwm->periph_regs);
pwm->sys_clk = devm_clk_get(&pdev->dev, "sys");
if (IS_ERR(pwm->sys_clk)) {
dev_err(&pdev->dev, "failed to get system clock\n");
return PTR_ERR(pwm->sys_clk);
}
pwm->pwm_clk = devm_clk_get(&pdev->dev, "pwm");
if (IS_ERR(pwm->pwm_clk)) {
dev_err(&pdev->dev, "failed to get pwm clock\n");
return PTR_ERR(pwm->pwm_clk);
}
ret = clk_prepare_enable(pwm->sys_clk);
if (ret < 0) {
dev_err(&pdev->dev, "could not prepare or enable sys clock\n");
return ret;
}
ret = clk_prepare_enable(pwm->pwm_clk);
if (ret < 0) {
dev_err(&pdev->dev, "could not prepare or enable pwm clock\n");
goto disable_sysclk;
}
pwm->chip.dev = &pdev->dev;
pwm->chip.ops = &img_pwm_ops;
pwm->chip.base = -1;
pwm->chip.npwm = 4;
ret = pwmchip_add(&pwm->chip);
if (ret < 0) {
dev_err(&pdev->dev, "pwmchip_add failed: %d\n", ret);
goto disable_pwmclk;
}
platform_set_drvdata(pdev, pwm);
return 0;
disable_pwmclk:
clk_disable_unprepare(pwm->pwm_clk);
disable_sysclk:
clk_disable_unprepare(pwm->sys_clk);
return ret;
}
static int img_pwm_remove(struct platform_device *pdev)
{
struct img_pwm_chip *pwm_chip = platform_get_drvdata(pdev);
u32 val;
unsigned int i;
for (i = 0; i < pwm_chip->chip.npwm; i++) {
val = img_pwm_readl(pwm_chip, PWM_CTRL_CFG);
val &= ~BIT(i);
img_pwm_writel(pwm_chip, PWM_CTRL_CFG, val);
}
clk_disable_unprepare(pwm_chip->pwm_clk);
clk_disable_unprepare(pwm_chip->sys_clk);
return pwmchip_remove(&pwm_chip->chip);
}
static const struct of_device_id img_pwm_of_match[] = {
{ .compatible = "img,pistachio-pwm", },
{ }
};
MODULE_DEVICE_TABLE(of, img_pwm_of_match);
static struct platform_driver img_pwm_driver = {
.driver = {
.name = "img-pwm",
.of_match_table = img_pwm_of_match,
},
.probe = img_pwm_probe,
.remove = img_pwm_remove,
};
module_platform_driver(img_pwm_driver);
MODULE_AUTHOR("Sai Masarapu <Sai.Masarapu@imgtec.com>");
MODULE_DESCRIPTION("Imagination Technologies PWM DAC driver");
MODULE_LICENSE("GPL v2");
...@@ -57,6 +57,7 @@ struct sti_pwm_chip { ...@@ -57,6 +57,7 @@ struct sti_pwm_chip {
struct regmap_field *pwm_int_en; struct regmap_field *pwm_int_en;
struct pwm_chip chip; struct pwm_chip chip;
struct pwm_device *cur; struct pwm_device *cur;
unsigned long configured;
unsigned int en_count; unsigned int en_count;
struct mutex sti_pwm_lock; /* To sync between enable/disable calls */ struct mutex sti_pwm_lock; /* To sync between enable/disable calls */
void __iomem *mmio; void __iomem *mmio;
...@@ -102,24 +103,6 @@ static int sti_pwm_get_prescale(struct sti_pwm_chip *pc, unsigned long period, ...@@ -102,24 +103,6 @@ static int sti_pwm_get_prescale(struct sti_pwm_chip *pc, unsigned long period,
return 0; return 0;
} }
/* Calculate the number of PWM devices configured with a period. */
static unsigned int sti_pwm_count_configured(struct pwm_chip *chip)
{
struct pwm_device *pwm;
unsigned int ncfg = 0;
unsigned int i;
for (i = 0; i < chip->npwm; i++) {
pwm = &chip->pwms[i];
if (test_bit(PWMF_REQUESTED, &pwm->flags)) {
if (pwm_get_period(pwm))
ncfg++;
}
}
return ncfg;
}
/* /*
* For STiH4xx PWM IP, the PWM period is fixed to 256 local clock cycles. * For STiH4xx PWM IP, the PWM period is fixed to 256 local clock cycles.
* The only way to change the period (apart from changing the PWM input clock) * The only way to change the period (apart from changing the PWM input clock)
...@@ -141,7 +124,7 @@ static int sti_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, ...@@ -141,7 +124,7 @@ static int sti_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
unsigned int ncfg; unsigned int ncfg;
bool period_same = false; bool period_same = false;
ncfg = sti_pwm_count_configured(chip); ncfg = hweight_long(pc->configured);
if (ncfg) if (ncfg)
period_same = (period_ns == pwm_get_period(cur)); period_same = (period_ns == pwm_get_period(cur));
...@@ -197,6 +180,7 @@ static int sti_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, ...@@ -197,6 +180,7 @@ static int sti_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
ret = regmap_field_write(pc->pwm_int_en, 0); ret = regmap_field_write(pc->pwm_int_en, 0);
set_bit(pwm->hwpwm, &pc->configured);
pc->cur = pwm; pc->cur = pwm;
dev_dbg(dev, "prescale:%u, period:%i, duty:%i, pwmvalx:%u\n", dev_dbg(dev, "prescale:%u, period:%i, duty:%i, pwmvalx:%u\n",
...@@ -254,10 +238,18 @@ static void sti_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) ...@@ -254,10 +238,18 @@ static void sti_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
mutex_unlock(&pc->sti_pwm_lock); mutex_unlock(&pc->sti_pwm_lock);
} }
static void sti_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct sti_pwm_chip *pc = to_sti_pwmchip(chip);
clear_bit(pwm->hwpwm, &pc->configured);
}
static const struct pwm_ops sti_pwm_ops = { static const struct pwm_ops sti_pwm_ops = {
.config = sti_pwm_config, .config = sti_pwm_config,
.enable = sti_pwm_enable, .enable = sti_pwm_enable,
.disable = sti_pwm_disable, .disable = sti_pwm_disable,
.free = sti_pwm_free,
.owner = THIS_MODULE, .owner = THIS_MODULE,
}; };
......
/*
* Driver for Allwinner sun4i Pulse Width Modulation Controller
*
* Copyright (C) 2014 Alexandre Belloni <alexandre.belloni@free-electrons.com>
*
* Licensed under GPLv2.
*/
#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pwm.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/time.h>
#define PWM_CTRL_REG 0x0
#define PWM_CH_PRD_BASE 0x4
#define PWM_CH_PRD_OFFSET 0x4
#define PWM_CH_PRD(ch) (PWM_CH_PRD_BASE + PWM_CH_PRD_OFFSET * (ch))
#define PWMCH_OFFSET 15
#define PWM_PRESCAL_MASK GENMASK(3, 0)
#define PWM_PRESCAL_OFF 0
#define PWM_EN BIT(4)
#define PWM_ACT_STATE BIT(5)
#define PWM_CLK_GATING BIT(6)
#define PWM_MODE BIT(7)
#define PWM_PULSE BIT(8)
#define PWM_BYPASS BIT(9)
#define PWM_RDY_BASE 28
#define PWM_RDY_OFFSET 1
#define PWM_RDY(ch) BIT(PWM_RDY_BASE + PWM_RDY_OFFSET * (ch))
#define PWM_PRD(prd) (((prd) - 1) << 16)
#define PWM_PRD_MASK GENMASK(15, 0)
#define PWM_DTY_MASK GENMASK(15, 0)
#define BIT_CH(bit, chan) ((bit) << ((chan) * PWMCH_OFFSET))
static const u32 prescaler_table[] = {
120,
180,
240,
360,
480,
0,
0,
0,
12000,
24000,
36000,
48000,
72000,
0,
0,
0, /* Actually 1 but tested separately */
};
struct sun4i_pwm_data {
bool has_prescaler_bypass;
bool has_rdy;
};
struct sun4i_pwm_chip {
struct pwm_chip chip;
struct clk *clk;
void __iomem *base;
spinlock_t ctrl_lock;
const struct sun4i_pwm_data *data;
};
static inline struct sun4i_pwm_chip *to_sun4i_pwm_chip(struct pwm_chip *chip)
{
return container_of(chip, struct sun4i_pwm_chip, chip);
}
static inline u32 sun4i_pwm_readl(struct sun4i_pwm_chip *chip,
unsigned long offset)
{
return readl(chip->base + offset);
}
static inline void sun4i_pwm_writel(struct sun4i_pwm_chip *chip,
u32 val, unsigned long offset)
{
writel(val, chip->base + offset);
}
static int sun4i_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
int duty_ns, int period_ns)
{
struct sun4i_pwm_chip *sun4i_pwm = to_sun4i_pwm_chip(chip);
u32 prd, dty, val, clk_gate;
u64 clk_rate, div = 0;
unsigned int prescaler = 0;
int err;
clk_rate = clk_get_rate(sun4i_pwm->clk);
if (sun4i_pwm->data->has_prescaler_bypass) {
/* First, test without any prescaler when available */
prescaler = PWM_PRESCAL_MASK;
/*
* When not using any prescaler, the clock period in nanoseconds
* is not an integer so round it half up instead of
* truncating to get less surprising values.
*/
div = clk_rate * period_ns + NSEC_PER_SEC/2;
do_div(div, NSEC_PER_SEC);
if (div - 1 > PWM_PRD_MASK)
prescaler = 0;
}
if (prescaler == 0) {
/* Go up from the first divider */
for (prescaler = 0; prescaler < PWM_PRESCAL_MASK; prescaler++) {
if (!prescaler_table[prescaler])
continue;
div = clk_rate;
do_div(div, prescaler_table[prescaler]);
div = div * period_ns;
do_div(div, NSEC_PER_SEC);
if (div - 1 <= PWM_PRD_MASK)
break;
}
if (div - 1 > PWM_PRD_MASK) {
dev_err(chip->dev, "period exceeds the maximum value\n");
return -EINVAL;
}
}
prd = div;
div *= duty_ns;
do_div(div, period_ns);
dty = div;
err = clk_prepare_enable(sun4i_pwm->clk);
if (err) {
dev_err(chip->dev, "failed to enable PWM clock\n");
return err;
}
spin_lock(&sun4i_pwm->ctrl_lock);
val = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG);
if (sun4i_pwm->data->has_rdy && (val & PWM_RDY(pwm->hwpwm))) {
spin_unlock(&sun4i_pwm->ctrl_lock);
clk_disable_unprepare(sun4i_pwm->clk);
return -EBUSY;
}
clk_gate = val & BIT_CH(PWM_CLK_GATING, pwm->hwpwm);
if (clk_gate) {
val &= ~BIT_CH(PWM_CLK_GATING, pwm->hwpwm);
sun4i_pwm_writel(sun4i_pwm, val, PWM_CTRL_REG);
}
val = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG);
val &= ~BIT_CH(PWM_PRESCAL_MASK, pwm->hwpwm);
val |= BIT_CH(prescaler, pwm->hwpwm);
sun4i_pwm_writel(sun4i_pwm, val, PWM_CTRL_REG);
val = (dty & PWM_DTY_MASK) | PWM_PRD(prd);
sun4i_pwm_writel(sun4i_pwm, val, PWM_CH_PRD(pwm->hwpwm));
if (clk_gate) {
val = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG);
val |= clk_gate;
sun4i_pwm_writel(sun4i_pwm, val, PWM_CTRL_REG);
}
spin_unlock(&sun4i_pwm->ctrl_lock);
clk_disable_unprepare(sun4i_pwm->clk);
return 0;
}
static int sun4i_pwm_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm,
enum pwm_polarity polarity)
{
struct sun4i_pwm_chip *sun4i_pwm = to_sun4i_pwm_chip(chip);
u32 val;
int ret;
ret = clk_prepare_enable(sun4i_pwm->clk);
if (ret) {
dev_err(chip->dev, "failed to enable PWM clock\n");
return ret;
}
spin_lock(&sun4i_pwm->ctrl_lock);
val = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG);
if (polarity != PWM_POLARITY_NORMAL)
val &= ~BIT_CH(PWM_ACT_STATE, pwm->hwpwm);
else
val |= BIT_CH(PWM_ACT_STATE, pwm->hwpwm);
sun4i_pwm_writel(sun4i_pwm, val, PWM_CTRL_REG);
spin_unlock(&sun4i_pwm->ctrl_lock);
clk_disable_unprepare(sun4i_pwm->clk);
return 0;
}
static int sun4i_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct sun4i_pwm_chip *sun4i_pwm = to_sun4i_pwm_chip(chip);
u32 val;
int ret;
ret = clk_prepare_enable(sun4i_pwm->clk);
if (ret) {
dev_err(chip->dev, "failed to enable PWM clock\n");
return ret;
}
spin_lock(&sun4i_pwm->ctrl_lock);
val = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG);
val |= BIT_CH(PWM_EN, pwm->hwpwm);
val |= BIT_CH(PWM_CLK_GATING, pwm->hwpwm);
sun4i_pwm_writel(sun4i_pwm, val, PWM_CTRL_REG);
spin_unlock(&sun4i_pwm->ctrl_lock);
return 0;
}
static void sun4i_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct sun4i_pwm_chip *sun4i_pwm = to_sun4i_pwm_chip(chip);
u32 val;
spin_lock(&sun4i_pwm->ctrl_lock);
val = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG);
val &= ~BIT_CH(PWM_EN, pwm->hwpwm);
val &= ~BIT_CH(PWM_CLK_GATING, pwm->hwpwm);
sun4i_pwm_writel(sun4i_pwm, val, PWM_CTRL_REG);
spin_unlock(&sun4i_pwm->ctrl_lock);
clk_disable_unprepare(sun4i_pwm->clk);
}
static const struct pwm_ops sun4i_pwm_ops = {
.config = sun4i_pwm_config,
.set_polarity = sun4i_pwm_set_polarity,
.enable = sun4i_pwm_enable,
.disable = sun4i_pwm_disable,
.owner = THIS_MODULE,
};
static const struct sun4i_pwm_data sun4i_pwm_data_a10 = {
.has_prescaler_bypass = false,
.has_rdy = false,
};
static const struct sun4i_pwm_data sun4i_pwm_data_a20 = {
.has_prescaler_bypass = true,
.has_rdy = true,
};
static const struct of_device_id sun4i_pwm_dt_ids[] = {
{
.compatible = "allwinner,sun4i-a10-pwm",
.data = &sun4i_pwm_data_a10,
}, {
.compatible = "allwinner,sun7i-a20-pwm",
.data = &sun4i_pwm_data_a20,
}, {
/* sentinel */
},
};
MODULE_DEVICE_TABLE(of, sun4i_pwm_dt_ids);
static int sun4i_pwm_probe(struct platform_device *pdev)
{
struct sun4i_pwm_chip *pwm;
struct resource *res;
u32 val;
int i, ret;
const struct of_device_id *match;
match = of_match_device(sun4i_pwm_dt_ids, &pdev->dev);
pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL);
if (!pwm)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
pwm->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(pwm->base))
return PTR_ERR(pwm->base);
pwm->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(pwm->clk))
return PTR_ERR(pwm->clk);
pwm->chip.dev = &pdev->dev;
pwm->chip.ops = &sun4i_pwm_ops;
pwm->chip.base = -1;
pwm->chip.npwm = 2;
pwm->chip.can_sleep = true;
pwm->chip.of_xlate = of_pwm_xlate_with_flags;
pwm->chip.of_pwm_n_cells = 3;
pwm->data = match->data;
spin_lock_init(&pwm->ctrl_lock);
ret = pwmchip_add(&pwm->chip);
if (ret < 0) {
dev_err(&pdev->dev, "failed to add PWM chip: %d\n", ret);
return ret;
}
platform_set_drvdata(pdev, pwm);
ret = clk_prepare_enable(pwm->clk);
if (ret) {
dev_err(&pdev->dev, "failed to enable PWM clock\n");
goto clk_error;
}
val = sun4i_pwm_readl(pwm, PWM_CTRL_REG);
for (i = 0; i < pwm->chip.npwm; i++)
if (!(val & BIT_CH(PWM_ACT_STATE, i)))
pwm->chip.pwms[i].polarity = PWM_POLARITY_INVERSED;
clk_disable_unprepare(pwm->clk);
return 0;
clk_error:
pwmchip_remove(&pwm->chip);
return ret;
}
static int sun4i_pwm_remove(struct platform_device *pdev)
{
struct sun4i_pwm_chip *pwm = platform_get_drvdata(pdev);
return pwmchip_remove(&pwm->chip);
}
static struct platform_driver sun4i_pwm_driver = {
.driver = {
.name = "sun4i-pwm",
.of_match_table = sun4i_pwm_dt_ids,
},
.probe = sun4i_pwm_probe,
.remove = sun4i_pwm_remove,
};
module_platform_driver(sun4i_pwm_driver);
MODULE_ALIAS("platform:sun4i-pwm");
MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@free-electrons.com>");
MODULE_DESCRIPTION("Allwinner sun4i PWM driver");
MODULE_LICENSE("GPL v2");
...@@ -87,7 +87,7 @@ static int tegra_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, ...@@ -87,7 +87,7 @@ static int tegra_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
* cycles at the PWM clock rate will take period_ns nanoseconds. * cycles at the PWM clock rate will take period_ns nanoseconds.
*/ */
rate = clk_get_rate(pc->clk) >> PWM_DUTY_WIDTH; rate = clk_get_rate(pc->clk) >> PWM_DUTY_WIDTH;
hz = 1000000000ul / period_ns; hz = NSEC_PER_SEC / period_ns;
rate = (rate + (hz / 2)) / hz; rate = (rate + (hz / 2)) / hz;
......
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