Merge tag 'pwm/for-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
 "There are two new drivers, one for the BCM2835 (Raspberry Pi) and one
  used in conjunction with the LCD controller on various Atmel SoCs.
  The Samsung PWM driver can now be built for 64-bit ARM (Exynos7).

  A couple of fixes have been applied to the FTM PWM driver and system
  sleep support was added"

* tag 'pwm/for-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm:
  pwm: atmel-hlcdc: add at91sam9x5 and sama5d3 errata handling
  pwm: ftm: Add Power Management support for FTM PWM
  pwm: ftm: Add regmap rbtree type cache support
  pwm: ftm: Correctly track usage count
  pwm: samsung: Allow Samsung PWM driver to be enabled on Exynos7
  pwm: add DT bindings documentation for atmel-hlcdc-pwm driver
  pwm: add support for atmel-hlcdc-pwm device
  pwm: Add BCM2835 PWM driver

1 files changed, 299 insertions, 0 deletions

diff --git a/drivers/pwm/pwm-atmel-hlcdc.c b/drivers/pwm/pwm-atmel-hlcdc.c
new file mode 100644
index 000000000000..e7a785fadcdf
--- /dev/null
+++ b/drivers/pwm/pwm-atmel-hlcdc.c
@@ -0,0 +1,299 @@
+/*
+ * Copyright (C) 2014 Free Electrons
+ * Copyright (C) 2014 Atmel
+ *
+ * Author: Boris BREZILLON <boris.brezillon@free-electrons.com>
+ *
+ * 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.
+ *
+ * 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/clk.h>
+#include <linux/delay.h>
+#include <linux/mfd/atmel-hlcdc.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/regmap.h>
+
+#define ATMEL_HLCDC_PWMCVAL_MASK	GENMASK(15, 8)
+#define ATMEL_HLCDC_PWMCVAL(x)		(((x) << 8) & ATMEL_HLCDC_PWMCVAL_MASK)
+#define ATMEL_HLCDC_PWMPOL		BIT(4)
+#define ATMEL_HLCDC_PWMPS_MASK		GENMASK(2, 0)
+#define ATMEL_HLCDC_PWMPS_MAX		0x6
+#define ATMEL_HLCDC_PWMPS(x)		((x) & ATMEL_HLCDC_PWMPS_MASK)
+
+struct atmel_hlcdc_pwm_errata {
+	bool slow_clk_erratum;
+	bool div1_clk_erratum;
+};
+
+struct atmel_hlcdc_pwm {
+	struct pwm_chip chip;
+	struct atmel_hlcdc *hlcdc;
+	struct clk *cur_clk;
+	const struct atmel_hlcdc_pwm_errata *errata;
+};
+
+static inline struct atmel_hlcdc_pwm *to_atmel_hlcdc_pwm(struct pwm_chip *chip)
+{
+	return container_of(chip, struct atmel_hlcdc_pwm, chip);
+}
+
+static int atmel_hlcdc_pwm_config(struct pwm_chip *c,
+				  struct pwm_device *pwm,
+				  int duty_ns, int period_ns)
+{
+	struct atmel_hlcdc_pwm *chip = to_atmel_hlcdc_pwm(c);
+	struct atmel_hlcdc *hlcdc = chip->hlcdc;
+	struct clk *new_clk = hlcdc->slow_clk;
+	u64 pwmcval = duty_ns * 256;
+	unsigned long clk_freq;
+	u64 clk_period_ns;
+	u32 pwmcfg;
+	int pres;
+
+	if (!chip->errata || !chip->errata->slow_clk_erratum) {
+		clk_freq = clk_get_rate(new_clk);
+		clk_period_ns = (u64)NSEC_PER_SEC * 256;
+		do_div(clk_period_ns, clk_freq);
+	}
+
+	/* Errata: cannot use slow clk on some IP revisions */
+	if ((chip->errata && chip->errata->slow_clk_erratum) ||
+	    clk_period_ns > period_ns) {
+		new_clk = hlcdc->sys_clk;
+		clk_freq = clk_get_rate(new_clk);
+		clk_period_ns = (u64)NSEC_PER_SEC * 256;
+		do_div(clk_period_ns, clk_freq);
+	}
+
+	for (pres = 0; pres <= ATMEL_HLCDC_PWMPS_MAX; pres++) {
+		/* Errata: cannot divide by 1 on some IP revisions */
+		if (!pres && chip->errata && chip->errata->div1_clk_erratum)
+			continue;
+
+		if ((clk_period_ns << pres) >= period_ns)
+			break;
+	}
+
+	if (pres > ATMEL_HLCDC_PWMPS_MAX)
+		return -EINVAL;
+
+	pwmcfg = ATMEL_HLCDC_PWMPS(pres);
+
+	if (new_clk != chip->cur_clk) {
+		u32 gencfg = 0;
+		int ret;
+
+		ret = clk_prepare_enable(new_clk);
+		if (ret)
+			return ret;
+
+		clk_disable_unprepare(chip->cur_clk);
+		chip->cur_clk = new_clk;
+
+		if (new_clk == hlcdc->sys_clk)
+			gencfg = ATMEL_HLCDC_CLKPWMSEL;
+
+		ret = regmap_update_bits(hlcdc->regmap, ATMEL_HLCDC_CFG(0),
+					 ATMEL_HLCDC_CLKPWMSEL, gencfg);
+		if (ret)
+			return ret;
+	}
+
+	do_div(pwmcval, period_ns);
+
+	/*
+	 * The PWM duty cycle is configurable from 0/256 to 255/256 of the
+	 * period cycle. Hence we can't set a duty cycle occupying the
+	 * whole period cycle if we're asked to.
+	 * Set it to 255 if pwmcval is greater than 256.
+	 */
+	if (pwmcval > 255)
+		pwmcval = 255;
+
+	pwmcfg |= ATMEL_HLCDC_PWMCVAL(pwmcval);
+
+	return regmap_update_bits(hlcdc->regmap, ATMEL_HLCDC_CFG(6),
+				  ATMEL_HLCDC_PWMCVAL_MASK |
+				  ATMEL_HLCDC_PWMPS_MASK,
+				  pwmcfg);
+}
+
+static int atmel_hlcdc_pwm_set_polarity(struct pwm_chip *c,
+					struct pwm_device *pwm,
+					enum pwm_polarity polarity)
+{
+	struct atmel_hlcdc_pwm *chip = to_atmel_hlcdc_pwm(c);
+	struct atmel_hlcdc *hlcdc = chip->hlcdc;
+	u32 cfg = 0;
+
+	if (polarity == PWM_POLARITY_NORMAL)
+		cfg = ATMEL_HLCDC_PWMPOL;
+
+	return regmap_update_bits(hlcdc->regmap, ATMEL_HLCDC_CFG(6),
+				  ATMEL_HLCDC_PWMPOL, cfg);
+}
+
+static int atmel_hlcdc_pwm_enable(struct pwm_chip *c, struct pwm_device *pwm)
+{
+	struct atmel_hlcdc_pwm *chip = to_atmel_hlcdc_pwm(c);
+	struct atmel_hlcdc *hlcdc = chip->hlcdc;
+	u32 status;
+	int ret;
+
+	ret = regmap_write(hlcdc->regmap, ATMEL_HLCDC_EN, ATMEL_HLCDC_PWM);
+	if (ret)
+		return ret;
+
+	while (true) {
+		ret = regmap_read(hlcdc->regmap, ATMEL_HLCDC_SR, &status);
+		if (ret)
+			return ret;
+
+		if ((status & ATMEL_HLCDC_PWM) != 0)
+			break;
+
+		usleep_range(1, 10);
+	}
+
+	return 0;
+}
+
+static void atmel_hlcdc_pwm_disable(struct pwm_chip *c,
+				    struct pwm_device *pwm)
+{
+	struct atmel_hlcdc_pwm *chip = to_atmel_hlcdc_pwm(c);
+	struct atmel_hlcdc *hlcdc = chip->hlcdc;
+	u32 status;
+	int ret;
+
+	ret = regmap_write(hlcdc->regmap, ATMEL_HLCDC_DIS, ATMEL_HLCDC_PWM);
+	if (ret)
+		return;
+
+	while (true) {
+		ret = regmap_read(hlcdc->regmap, ATMEL_HLCDC_SR, &status);
+		if (ret)
+			return;
+
+		if ((status & ATMEL_HLCDC_PWM) == 0)
+			break;
+
+		usleep_range(1, 10);
+	}
+}
+
+static const struct pwm_ops atmel_hlcdc_pwm_ops = {
+	.config = atmel_hlcdc_pwm_config,
+	.set_polarity = atmel_hlcdc_pwm_set_polarity,
+	.enable = atmel_hlcdc_pwm_enable,
+	.disable = atmel_hlcdc_pwm_disable,
+	.owner = THIS_MODULE,
+};
+
+static const struct atmel_hlcdc_pwm_errata atmel_hlcdc_pwm_at91sam9x5_errata = {
+	.slow_clk_erratum = true,
+};
+
+static const struct atmel_hlcdc_pwm_errata atmel_hlcdc_pwm_sama5d3_errata = {
+	.div1_clk_erratum = true,
+};
+
+static const struct of_device_id atmel_hlcdc_dt_ids[] = {
+	{
+		.compatible = "atmel,at91sam9x5-hlcdc",
+		.data = &atmel_hlcdc_pwm_at91sam9x5_errata,
+	},
+	{
+		.compatible = "atmel,sama5d3-hlcdc",
+		.data = &atmel_hlcdc_pwm_sama5d3_errata,
+	},
+	{ /* sentinel */ },
+};
+
+static int atmel_hlcdc_pwm_probe(struct platform_device *pdev)
+{
+	const struct of_device_id *match;
+	struct device *dev = &pdev->dev;
+	struct atmel_hlcdc_pwm *chip;
+	struct atmel_hlcdc *hlcdc;
+	int ret;
+
+	hlcdc = dev_get_drvdata(dev->parent);
+
+	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	ret = clk_prepare_enable(hlcdc->periph_clk);
+	if (ret)
+		return ret;
+
+	match = of_match_node(atmel_hlcdc_dt_ids, dev->parent->of_node);
+	if (match)
+		chip->errata = match->data;
+
+	chip->hlcdc = hlcdc;
+	chip->chip.ops = &atmel_hlcdc_pwm_ops;
+	chip->chip.dev = dev;
+	chip->chip.base = -1;
+	chip->chip.npwm = 1;
+	chip->chip.of_xlate = of_pwm_xlate_with_flags;
+	chip->chip.of_pwm_n_cells = 3;
+	chip->chip.can_sleep = 1;
+
+	ret = pwmchip_add(&chip->chip);
+	if (ret) {
+		clk_disable_unprepare(hlcdc->periph_clk);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, chip);
+
+	return 0;
+}
+
+static int atmel_hlcdc_pwm_remove(struct platform_device *pdev)
+{
+	struct atmel_hlcdc_pwm *chip = platform_get_drvdata(pdev);
+	int ret;
+
+	ret = pwmchip_remove(&chip->chip);
+	if (ret)
+		return ret;
+
+	clk_disable_unprepare(chip->hlcdc->periph_clk);
+
+	return 0;
+}
+
+static const struct of_device_id atmel_hlcdc_pwm_dt_ids[] = {
+	{ .compatible = "atmel,hlcdc-pwm" },
+	{ /* sentinel */ },
+};
+
+static struct platform_driver atmel_hlcdc_pwm_driver = {
+	.driver = {
+		.name = "atmel-hlcdc-pwm",
+		.of_match_table = atmel_hlcdc_pwm_dt_ids,
+	},
+	.probe = atmel_hlcdc_pwm_probe,
+	.remove = atmel_hlcdc_pwm_remove,
+};
+module_platform_driver(atmel_hlcdc_pwm_driver);
+
+MODULE_ALIAS("platform:atmel-hlcdc-pwm");
+MODULE_AUTHOR("Boris Brezillon <boris.brezillon@free-electrons.com>");
+MODULE_DESCRIPTION("Atmel HLCDC PWM driver");
+MODULE_LICENSE("GPL v2");