File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/mfd/atmel-hlcdc.c b/drivers/mfd/atmel-hlcdc.c
new file mode 100644
index 0000000..c216c3a
--- /dev/null
+++ b/drivers/mfd/atmel-hlcdc.c
@@ -0,0 +1,167 @@
+/*
+ * 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/iopoll.h>
+#include <linux/mfd/atmel-hlcdc.h>
+#include <linux/mfd/core.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#define ATMEL_HLCDC_REG_MAX		(0x4000 - 0x4)
+
+struct atmel_hlcdc_regmap {
+	void __iomem *regs;
+};
+
+static const struct mfd_cell atmel_hlcdc_cells[] = {
+	{
+		.name = "atmel-hlcdc-pwm",
+		.of_compatible = "atmel,hlcdc-pwm",
+	},
+	{
+		.name = "atmel-hlcdc-dc",
+		.of_compatible = "atmel,hlcdc-display-controller",
+	},
+};
+
+static int regmap_atmel_hlcdc_reg_write(void *context, unsigned int reg,
+					unsigned int val)
+{
+	struct atmel_hlcdc_regmap *hregmap = context;
+
+	if (reg <= ATMEL_HLCDC_DIS) {
+		u32 status;
+
+		readl_poll_timeout_atomic(hregmap->regs + ATMEL_HLCDC_SR,
+					  status, !(status & ATMEL_HLCDC_SIP),
+					  1, 100);
+	}
+
+	writel(val, hregmap->regs + reg);
+
+	return 0;
+}
+
+static int regmap_atmel_hlcdc_reg_read(void *context, unsigned int reg,
+				       unsigned int *val)
+{
+	struct atmel_hlcdc_regmap *hregmap = context;
+
+	*val = readl(hregmap->regs + reg);
+
+	return 0;
+}
+
+static const struct regmap_config atmel_hlcdc_regmap_config = {
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.max_register = ATMEL_HLCDC_REG_MAX,
+	.reg_write = regmap_atmel_hlcdc_reg_write,
+	.reg_read = regmap_atmel_hlcdc_reg_read,
+	.fast_io = true,
+};
+
+static int atmel_hlcdc_probe(struct platform_device *pdev)
+{
+	struct atmel_hlcdc_regmap *hregmap;
+	struct device *dev = &pdev->dev;
+	struct atmel_hlcdc *hlcdc;
+	struct resource *res;
+
+	hregmap = devm_kzalloc(dev, sizeof(*hregmap), GFP_KERNEL);
+	if (!hregmap)
+		return -ENOMEM;
+
+	hlcdc = devm_kzalloc(dev, sizeof(*hlcdc), GFP_KERNEL);
+	if (!hlcdc)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	hregmap->regs = devm_ioremap_resource(dev, res);
+	if (IS_ERR(hregmap->regs))
+		return PTR_ERR(hregmap->regs);
+
+	hlcdc->irq = platform_get_irq(pdev, 0);
+	if (hlcdc->irq < 0)
+		return hlcdc->irq;
+
+	hlcdc->periph_clk = devm_clk_get(dev, "periph_clk");
+	if (IS_ERR(hlcdc->periph_clk)) {
+		dev_err(dev, "failed to get peripheral clock\n");
+		return PTR_ERR(hlcdc->periph_clk);
+	}
+
+	hlcdc->sys_clk = devm_clk_get(dev, "sys_clk");
+	if (IS_ERR(hlcdc->sys_clk)) {
+		dev_err(dev, "failed to get system clock\n");
+		return PTR_ERR(hlcdc->sys_clk);
+	}
+
+	hlcdc->slow_clk = devm_clk_get(dev, "slow_clk");
+	if (IS_ERR(hlcdc->slow_clk)) {
+		dev_err(dev, "failed to get slow clock\n");
+		return PTR_ERR(hlcdc->slow_clk);
+	}
+
+	hlcdc->regmap = devm_regmap_init(dev, NULL, hregmap,
+					 &atmel_hlcdc_regmap_config);
+	if (IS_ERR(hlcdc->regmap))
+		return PTR_ERR(hlcdc->regmap);
+
+	dev_set_drvdata(dev, hlcdc);
+
+	return mfd_add_devices(dev, -1, atmel_hlcdc_cells,
+			       ARRAY_SIZE(atmel_hlcdc_cells),
+			       NULL, 0, NULL);
+}
+
+static int atmel_hlcdc_remove(struct platform_device *pdev)
+{
+	mfd_remove_devices(&pdev->dev);
+
+	return 0;
+}
+
+static const struct of_device_id atmel_hlcdc_match[] = {
+	{ .compatible = "atmel,at91sam9n12-hlcdc" },
+	{ .compatible = "atmel,at91sam9x5-hlcdc" },
+	{ .compatible = "atmel,sama5d2-hlcdc" },
+	{ .compatible = "atmel,sama5d3-hlcdc" },
+	{ .compatible = "atmel,sama5d4-hlcdc" },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, atmel_hlcdc_match);
+
+static struct platform_driver atmel_hlcdc_driver = {
+	.probe = atmel_hlcdc_probe,
+	.remove = atmel_hlcdc_remove,
+	.driver = {
+		.name = "atmel-hlcdc",
+		.of_match_table = atmel_hlcdc_match,
+	},
+};
+module_platform_driver(atmel_hlcdc_driver);
+
+MODULE_ALIAS("platform:atmel-hlcdc");
+MODULE_AUTHOR("Boris Brezillon <boris.brezillon@free-electrons.com>");
+MODULE_DESCRIPTION("Atmel HLCDC driver");
+MODULE_LICENSE("GPL v2");