diff options
Diffstat (limited to 'drivers/pwm/pwm-hibvt.c')
| -rw-r--r-- | drivers/pwm/pwm-hibvt.c | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-hibvt.c b/drivers/pwm/pwm-hibvt.c new file mode 100644 index 000000000000..d0e8f8542626 --- /dev/null +++ b/drivers/pwm/pwm-hibvt.c @@ -0,0 +1,271 @@ +/* + * PWM Controller Driver for HiSilicon BVT SoCs + * + * Copyright (c) 2016 HiSilicon Technologies Co., Ltd. + * + * 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, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/bitops.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/pwm.h> +#include <linux/reset.h> + +#define PWM_CFG0_ADDR(x) (((x) * 0x20) + 0x0) +#define PWM_CFG1_ADDR(x) (((x) * 0x20) + 0x4) +#define PWM_CFG2_ADDR(x) (((x) * 0x20) + 0x8) +#define PWM_CTRL_ADDR(x) (((x) * 0x20) + 0xC) + +#define PWM_ENABLE_SHIFT 0 +#define PWM_ENABLE_MASK BIT(0) + +#define PWM_POLARITY_SHIFT 1 +#define PWM_POLARITY_MASK BIT(1) + +#define PWM_KEEP_SHIFT 2 +#define PWM_KEEP_MASK BIT(2) + +#define PWM_PERIOD_MASK GENMASK(31, 0) +#define PWM_DUTY_MASK GENMASK(31, 0) + +struct hibvt_pwm_chip { + struct pwm_chip chip; + struct clk *clk; + void __iomem *base; + struct reset_control *rstc; +}; + +struct hibvt_pwm_soc { + u32 num_pwms; +}; + +static const struct hibvt_pwm_soc pwm_soc[2] = { + { .num_pwms = 4 }, + { .num_pwms = 8 }, +}; + +static inline struct hibvt_pwm_chip *to_hibvt_pwm_chip(struct pwm_chip *chip) +{ + return container_of(chip, struct hibvt_pwm_chip, chip); +} + +static void hibvt_pwm_set_bits(void __iomem *base, u32 offset, + u32 mask, u32 data) +{ + void __iomem *address = base + offset; + u32 value; + + value = readl(address); + value &= ~mask; + value |= (data & mask); + writel(value, address); +} + +static void hibvt_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct hibvt_pwm_chip *hi_pwm_chip = to_hibvt_pwm_chip(chip); + + hibvt_pwm_set_bits(hi_pwm_chip->base, PWM_CTRL_ADDR(pwm->hwpwm), + PWM_ENABLE_MASK, 0x1); +} + +static void hibvt_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct hibvt_pwm_chip *hi_pwm_chip = to_hibvt_pwm_chip(chip); + + hibvt_pwm_set_bits(hi_pwm_chip->base, PWM_CTRL_ADDR(pwm->hwpwm), + PWM_ENABLE_MASK, 0x0); +} + +static void hibvt_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, + int duty_cycle_ns, int period_ns) +{ + struct hibvt_pwm_chip *hi_pwm_chip = to_hibvt_pwm_chip(chip); + u32 freq, period, duty; + + freq = div_u64(clk_get_rate(hi_pwm_chip->clk), 1000000); + + period = div_u64(freq * period_ns, 1000); + duty = div_u64(period * duty_cycle_ns, period_ns); + + hibvt_pwm_set_bits(hi_pwm_chip->base, PWM_CFG0_ADDR(pwm->hwpwm), + PWM_PERIOD_MASK, period); + + hibvt_pwm_set_bits(hi_pwm_chip->base, PWM_CFG1_ADDR(pwm->hwpwm), + PWM_DUTY_MASK, duty); +} + +static void hibvt_pwm_set_polarity(struct pwm_chip *chip, + struct pwm_device *pwm, + enum pwm_polarity polarity) +{ + struct hibvt_pwm_chip *hi_pwm_chip = to_hibvt_pwm_chip(chip); + + if (polarity == PWM_POLARITY_INVERSED) + hibvt_pwm_set_bits(hi_pwm_chip->base, PWM_CTRL_ADDR(pwm->hwpwm), + PWM_POLARITY_MASK, (0x1 << PWM_POLARITY_SHIFT)); + else + hibvt_pwm_set_bits(hi_pwm_chip->base, PWM_CTRL_ADDR(pwm->hwpwm), + PWM_POLARITY_MASK, (0x0 << PWM_POLARITY_SHIFT)); +} + +static void hibvt_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_state *state) +{ + struct hibvt_pwm_chip *hi_pwm_chip = to_hibvt_pwm_chip(chip); + void __iomem *base; + u32 freq, value; + + freq = div_u64(clk_get_rate(hi_pwm_chip->clk), 1000000); + base = hi_pwm_chip->base; + + value = readl(base + PWM_CFG0_ADDR(pwm->hwpwm)); + state->period = div_u64(value * 1000, freq); + + value = readl(base + PWM_CFG1_ADDR(pwm->hwpwm)); + state->duty_cycle = div_u64(value * 1000, freq); + + value = readl(base + PWM_CTRL_ADDR(pwm->hwpwm)); + state->enabled = (PWM_ENABLE_MASK & value); +} + +static int hibvt_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_state *state) +{ + if (state->polarity != pwm->state.polarity) + hibvt_pwm_set_polarity(chip, pwm, state->polarity); + + if (state->period != pwm->state.period || + state->duty_cycle != pwm->state.duty_cycle) + hibvt_pwm_config(chip, pwm, state->duty_cycle, state->period); + + if (state->enabled != pwm->state.enabled) { + if (state->enabled) + hibvt_pwm_enable(chip, pwm); + else + hibvt_pwm_disable(chip, pwm); + } + + return 0; +} + +static struct pwm_ops hibvt_pwm_ops = { + .get_state = hibvt_pwm_get_state, + .apply = hibvt_pwm_apply, + + .owner = THIS_MODULE, +}; + +static int hibvt_pwm_probe(struct platform_device *pdev) +{ + const struct hibvt_pwm_soc *soc = + of_device_get_match_data(&pdev->dev); + struct hibvt_pwm_chip *pwm_chip; + struct resource *res; + int ret; + int i; + + pwm_chip = devm_kzalloc(&pdev->dev, sizeof(*pwm_chip), GFP_KERNEL); + if (pwm_chip == NULL) + return -ENOMEM; + + pwm_chip->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(pwm_chip->clk)) { + dev_err(&pdev->dev, "getting clock failed with %ld\n", + PTR_ERR(pwm_chip->clk)); + return PTR_ERR(pwm_chip->clk); + } + + pwm_chip->chip.ops = &hibvt_pwm_ops; + pwm_chip->chip.dev = &pdev->dev; + pwm_chip->chip.base = -1; + pwm_chip->chip.npwm = soc->num_pwms; + pwm_chip->chip.of_xlate = of_pwm_xlate_with_flags; + pwm_chip->chip.of_pwm_n_cells = 3; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + pwm_chip->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(pwm_chip->base)) + return PTR_ERR(pwm_chip->base); + + ret = clk_prepare_enable(pwm_chip->clk); + if (ret < 0) + return ret; + + pwm_chip->rstc = devm_reset_control_get(&pdev->dev, NULL); + if (IS_ERR(pwm_chip->rstc)) { + clk_disable_unprepare(pwm_chip->clk); + return PTR_ERR(pwm_chip->rstc); + } + + reset_control_assert(pwm_chip->rstc); + msleep(30); + reset_control_deassert(pwm_chip->rstc); + + ret = pwmchip_add(&pwm_chip->chip); + if (ret < 0) { + clk_disable_unprepare(pwm_chip->clk); + return ret; + } + + for (i = 0; i < pwm_chip->chip.npwm; i++) { + hibvt_pwm_set_bits(pwm_chip->base, PWM_CTRL_ADDR(i), + PWM_KEEP_MASK, (0x1 << PWM_KEEP_SHIFT)); + } + + platform_set_drvdata(pdev, pwm_chip); + + return 0; +} + +static int hibvt_pwm_remove(struct platform_device *pdev) +{ + struct hibvt_pwm_chip *pwm_chip; + + pwm_chip = platform_get_drvdata(pdev); + + reset_control_assert(pwm_chip->rstc); + msleep(30); + reset_control_deassert(pwm_chip->rstc); + + clk_disable_unprepare(pwm_chip->clk); + + return pwmchip_remove(&pwm_chip->chip); +} + +static const struct of_device_id hibvt_pwm_of_match[] = { + { .compatible = "hisilicon,hi3516cv300-pwm", .data = &pwm_soc[0] }, + { .compatible = "hisilicon,hi3519v100-pwm", .data = &pwm_soc[1] }, + { } +}; +MODULE_DEVICE_TABLE(of, hibvt_pwm_of_match); + +static struct platform_driver hibvt_pwm_driver = { + .driver = { + .name = "hibvt-pwm", + .of_match_table = hibvt_pwm_of_match, + }, + .probe = hibvt_pwm_probe, + .remove = hibvt_pwm_remove, +}; +module_platform_driver(hibvt_pwm_driver); + +MODULE_AUTHOR("Jian Yuan"); +MODULE_DESCRIPTION("HiSilicon BVT SoCs PWM driver"); +MODULE_LICENSE("GPL"); |