--- /dev/null
+/*
+ * 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");
projects / platform / kernel / linux-rpi.git / commitdiff