mfd: RK808: Add new mfd driver for RK808

The RK808 chip is a power management IC for multimedia and handheld
devices. It contains the following components:

- Regulators
- RTC
- Clkout

The RK808 core driver is registered as a platform driver and provides
communication through I2C with the host device for the different
components.

Signed-off-by: Chris Zhong <zyw@rock-chips.com>
Signed-off-by: Zhang Qing <zhangqing@rock-chips.com>
Tested-by: Heiko <heiko@sntech.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/mfd/rk808.c b/drivers/mfd/rk808.c
new file mode 100644
index 0000000..0324422
--- /dev/null
+++ b/drivers/mfd/rk808.c
@@ -0,0 +1,245 @@
+/*
+ * MFD core driver for Rockchip RK808
+ *
+ * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
+ *
+ * Author: Chris Zhong <zyw@rock-chips.com>
+ * Author: Zhang Qing <zhangqing@rock-chips.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ */
+
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/rk808.h>
+#include <linux/mfd/core.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+
+struct rk808_reg_data {
+	int addr;
+	int mask;
+	int value;
+};
+
+static const struct regmap_config rk808_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = RK808_IO_POL_REG,
+};
+
+static struct resource rtc_resources[] = {
+	{
+		.start  = RK808_IRQ_RTC_ALARM,
+		.end    = RK808_IRQ_RTC_ALARM,
+		.flags  = IORESOURCE_IRQ,
+	}
+};
+
+static const struct mfd_cell rk808s[] = {
+	{ .name = "rk808-clkout", },
+	{ .name = "rk808-regulator", },
+	{
+		.name = "rk808-rtc",
+		.num_resources = ARRAY_SIZE(rtc_resources),
+		.resources = &rtc_resources[0],
+	},
+};
+
+static const struct rk808_reg_data pre_init_reg[] = {
+	{ RK808_BUCK3_CONFIG_REG, BUCK_ILMIN_MASK,  BUCK_ILMIN_150MA },
+	{ RK808_BUCK4_CONFIG_REG, BUCK_ILMIN_MASK,  BUCK_ILMIN_200MA },
+	{ RK808_BOOST_CONFIG_REG, BOOST_ILMIN_MASK, BOOST_ILMIN_100MA },
+	{ RK808_BUCK1_CONFIG_REG, BUCK1_RATE_MASK,  BUCK_ILMIN_200MA },
+	{ RK808_BUCK2_CONFIG_REG, BUCK2_RATE_MASK,  BUCK_ILMIN_200MA },
+	{ RK808_VB_MON_REG,       MASK_ALL,         VB_LO_ACT |
+						    VB_LO_SEL_3500MV },
+};
+
+static const struct regmap_irq rk808_irqs[] = {
+	/* INT_STS */
+	[RK808_IRQ_VOUT_LO] = {
+		.mask = RK808_IRQ_VOUT_LO_MSK,
+		.reg_offset = 0,
+	},
+	[RK808_IRQ_VB_LO] = {
+		.mask = RK808_IRQ_VB_LO_MSK,
+		.reg_offset = 0,
+	},
+	[RK808_IRQ_PWRON] = {
+		.mask = RK808_IRQ_PWRON_MSK,
+		.reg_offset = 0,
+	},
+	[RK808_IRQ_PWRON_LP] = {
+		.mask = RK808_IRQ_PWRON_LP_MSK,
+		.reg_offset = 0,
+	},
+	[RK808_IRQ_HOTDIE] = {
+		.mask = RK808_IRQ_HOTDIE_MSK,
+		.reg_offset = 0,
+	},
+	[RK808_IRQ_RTC_ALARM] = {
+		.mask = RK808_IRQ_RTC_ALARM_MSK,
+		.reg_offset = 0,
+	},
+	[RK808_IRQ_RTC_PERIOD] = {
+		.mask = RK808_IRQ_RTC_PERIOD_MSK,
+		.reg_offset = 0,
+	},
+
+	/* INT_STS2 */
+	[RK808_IRQ_PLUG_IN_INT] = {
+		.mask = RK808_IRQ_PLUG_IN_INT_MSK,
+		.reg_offset = 1,
+	},
+	[RK808_IRQ_PLUG_OUT_INT] = {
+		.mask = RK808_IRQ_PLUG_OUT_INT_MSK,
+		.reg_offset = 1,
+	},
+};
+
+static struct regmap_irq_chip rk808_irq_chip = {
+	.name = "rk808",
+	.irqs = rk808_irqs,
+	.num_irqs = ARRAY_SIZE(rk808_irqs),
+	.num_regs = 2,
+	.irq_reg_stride = 2,
+	.status_base = RK808_INT_STS_REG1,
+	.mask_base = RK808_INT_STS_MSK_REG1,
+	.ack_base = RK808_INT_STS_REG1,
+	.init_ack_masked = true,
+};
+
+static struct i2c_client *rk808_i2c_client;
+static void rk808_device_shutdown(void)
+{
+	int ret;
+	struct rk808 *rk808 = i2c_get_clientdata(rk808_i2c_client);
+
+	if (!rk808) {
+		dev_warn(&rk808_i2c_client->dev,
+			 "have no rk808, so do nothing here\n");
+		return;
+	}
+
+	ret = regmap_update_bits(rk808->regmap,
+				 RK808_DEVCTRL_REG,
+				 DEV_OFF_RST, DEV_OFF_RST);
+	if (ret)
+		dev_err(&rk808_i2c_client->dev, "power off error!\n");
+}
+
+static int rk808_probe(struct i2c_client *client,
+		       const struct i2c_device_id *id)
+{
+	struct device_node *np = client->dev.of_node;
+	struct rk808 *rk808;
+	int pm_off = 0;
+	int ret;
+	int i;
+
+	if (!client->irq) {
+		dev_err(&client->dev, "No interrupt support, no core IRQ\n");
+		return -EINVAL;
+	}
+
+	rk808 = devm_kzalloc(&client->dev, sizeof(*rk808), GFP_KERNEL);
+	if (!rk808)
+		return -ENOMEM;
+
+	rk808->regmap = devm_regmap_init_i2c(client, &rk808_regmap_config);
+	if (IS_ERR(rk808->regmap)) {
+		dev_err(&client->dev, "regmap initialization failed\n");
+		return PTR_ERR(rk808->regmap);
+	}
+
+	for (i = 0; i < ARRAY_SIZE(pre_init_reg); i++) {
+		ret = regmap_update_bits(rk808->regmap, pre_init_reg[i].addr,
+					 pre_init_reg[i].mask,
+					 pre_init_reg[i].value);
+		if (ret) {
+			dev_err(&client->dev,
+				"0x%x write err\n", pre_init_reg[i].addr);
+			return ret;
+		}
+	}
+
+	ret = regmap_add_irq_chip(rk808->regmap, client->irq,
+				  IRQF_ONESHOT, -1,
+				  &rk808_irq_chip, &rk808->irq_data);
+	if (ret) {
+		dev_err(&client->dev, "Failed to add irq_chip %d\n", ret);
+		return ret;
+	}
+
+	rk808->i2c = client;
+	i2c_set_clientdata(client, rk808);
+
+	ret = mfd_add_devices(&client->dev, -1,
+			      rk808s, ARRAY_SIZE(rk808s),
+			      NULL, 0, regmap_irq_get_domain(rk808->irq_data));
+	if (ret) {
+		dev_err(&client->dev, "failed to add MFD devices %d\n", ret);
+		goto err_irq;
+	}
+
+	pm_off = of_property_read_bool(np,
+				"rockchip,system-power-controller");
+	if (pm_off && !pm_power_off) {
+		rk808_i2c_client = client;
+		pm_power_off = rk808_device_shutdown;
+	}
+
+	return 0;
+
+err_irq:
+	regmap_del_irq_chip(client->irq, rk808->irq_data);
+	return ret;
+}
+
+static int rk808_remove(struct i2c_client *client)
+{
+	struct rk808 *rk808 = i2c_get_clientdata(client);
+
+	regmap_del_irq_chip(client->irq, rk808->irq_data);
+	mfd_remove_devices(&client->dev);
+	pm_power_off = NULL;
+
+	return 0;
+}
+
+static struct of_device_id rk808_of_match[] = {
+	{ .compatible = "rockchip,rk808" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, rk808_of_match);
+
+static const struct i2c_device_id rk808_ids[] = {
+	{ "rk808" },
+	{ },
+};
+MODULE_DEVICE_TABLE(i2c, rk808_ids);
+
+static struct i2c_driver rk808_i2c_driver = {
+	.driver = {
+		.name = "rk808",
+		.of_match_table = rk808_of_match,
+	},
+	.probe    = rk808_probe,
+	.remove   = rk808_remove,
+	.id_table = rk808_ids,
+};
+
+module_i2c_driver(rk808_i2c_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Chris Zhong <zyw@rock-chips.com>");
+MODULE_AUTHOR("Zhang Qing <zhangqing@rock-chips.com>");
+MODULE_DESCRIPTION("RK808 PMIC driver");