OMAP2+ PM: Add support for TPS62361

TPS62361 is a new PMIC used with OMAP4460 on SDP4430 platform
to supply MPU VDD.
Rest of the VDDs continue to be supplied via TWL6030.

As part of this, the following have been moved to common
location in voltage.h
OMAP4_VP_CONFIG_ERROROFFSET, OMAP4_VP_VSTEPMIN_VSTEPMIN,
OMAP4_VP_VSTEPMAX_VSTEPMAX, OMAP4_VP_VLIMITTO_TIMEOUT_US

[nm@ti.com: cleaned up TPS to handle board variations]
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Vishwanath BS <vishwanath.bs@ti.com>

1 files changed, 340 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/omap_tps6236x.c b/arch/arm/mach-omap2/omap_tps6236x.c
new file mode 100644
index 0000000..9d49c2b
--- /dev/null
+++ b/arch/arm/mach-omap2/omap_tps6236x.c
@@ -0,0 +1,340 @@
+/*
+ * OMAP and TPS6236x specific initialization
+ *
+ * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
+ * Vishwanath BS
+ * Nishanth Menon
+ *
+ * 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.
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/gpio.h>
+#include <linux/i2c/twl.h>
+
+#include "pm.h"
+#include "vc.h"
+#include "mux.h"
+
+/* Voltage limits supported */
+#define MIN_VOLTAGE_TPS62360_62_UV	770000
+#define MAX_VOLTAGE_TPS62360_62_UV	1400000
+
+#define MIN_VOLTAGE_TPS62361_UV		500000
+#define MAX_VOLTAGE_TPS62361_UV		1770000
+
+#define MAX_VOLTAGE_RAMP_TPS6236X_UV	32000
+
+/*
+ * This is the voltage delta between 2 values in voltage register.
+ * when switching voltage V1 to V2, TPS62361 can ramp up or down
+ * initially with step sizes of 20mV with a last step of 10mV.
+ * In the case of TPS6236[0|2], it is a constant 10mV steps
+ * we choose the 10mV step for linearity when SR is configured.
+ */
+#define STEP_SIZE_TPS6236X		10000
+
+/* I2C access parameters */
+#define I2C_TPS6236X_SLAVE_ADDR		0x60
+
+#define DEF_SET_REG(VSEL0, VSEL1)	(((VSEL1) << 1| (VSEL0) << 0) & 0x3)
+#define REG_TPS6236X_SET_0		0x00
+#define REG_TPS6236X_SET_1		0x01
+#define REG_TPS6236X_SET_2		0x02
+#define REG_TPS6236X_SET_3		0x03
+#define REG_TPS6236X_CTRL		0x04
+#define REG_TPS6236X_TEMP		0x05
+#define REG_TPS6236X_RAMP_CTRL		0x06
+#define REG_TPS6236X_CHIP_ID0		0x08
+#define REG_TPS6236X_CHIP_ID1		0x09
+
+#define MODE_TPS6236X_AUTO_PFM_PWM	0x00
+#define MODE_TPS6236X_FORCE_PWM		BIT(7)
+
+/* We use Auto PFM/PWM mode currently seems to have the best trade off */
+#define VOLTAGE_PFM_MODE_VAL		MODE_TPS6236X_AUTO_PFM_PWM
+
+#define REG_TPS6236X_RAMP_CTRL_RMP_MASK	(0x7 << 5)
+#define REG_TPS6236X_RAMP_CTRL_EN_DISC	BIT(2)
+#define REG_TPS6236X_RAMP_CTRL_RAMP_PFM	BIT(1)
+
+#define REG_TPS6236X_CTRL_PD_EN		BIT(7)
+#define REG_TPS6236X_CTRL_PD_VSEL0	BIT(6)
+#define REG_TPS6236X_CTRL_PD_VSEL1	BIT(5)
+
+/* TWL usage */
+#define TWL6030_REG_SYSEN_CFG_GRP			0xB3
+#define TWL6030_BIT_APE_GRP				BIT(0)
+
+/* Voltage params of the attached device (all in uV) */
+static unsigned long	voltage_min;
+static unsigned long	voltage_max;
+
+/* Which register do we use by default? */
+static int __initdata	default_reg = -1;;
+
+/* Do we need to setup internal pullups? */
+static int __initdata	pd_vsel0 = -1;
+static int __initdata	pd_vsel1 = -1;
+
+static int __init _bd_setup(char *name,int gpio_vsel, int *pull, int *pd_vsel)
+{
+	int pull_dir;
+	int r;
+
+	if (gpio_vsel == -1) {
+		if (*pull != -1) {
+			*pd_vsel = (*pull == OMAP_PIN_OFF_OUTPUT_HIGH);
+			*pull = *pd_vsel;
+		} else {
+			*pull = 0;
+		}
+		return 0;
+	}
+
+	/* if we have a pull gpio, with bad dir, pull low */
+	if (*pull == -1 || (*pull != OMAP_PIN_OFF_OUTPUT_HIGH &&
+				*pull != OMAP_PIN_OFF_OUTPUT_LOW))
+		*pull = OMAP_PIN_OFF_OUTPUT_LOW;
+
+	r = omap_mux_init_gpio(gpio_vsel, *pull);
+	if (r) {
+		pr_err("%s: unable to mux gpio%d=%d\n", __func__,
+			gpio_vsel, r);
+		goto out;
+	}
+
+	pull_dir = (*pull == OMAP_PIN_OFF_OUTPUT_HIGH);
+	*pull = pull_dir;
+
+	r = gpio_request(gpio_vsel, name);
+	if (r) {
+		pr_err("%s: unable to req gpio%d=%d\n", __func__,
+			gpio_vsel, r);
+		goto out;
+	}
+	r = gpio_direction_output(gpio_vsel, pull_dir);
+	if (r) {
+		pr_err("%s: unable to pull[%d] gpio%d=%d\n", __func__,
+			gpio_vsel, pull_dir, r);
+		gpio_free(gpio_vsel);
+		goto out;
+	}
+out:
+	return r;
+}
+
+/* Convert the ramp voltage to ramp value. */
+static u8 __init tps6236x_ramp_value(unsigned long uv)
+{
+	if (!uv)
+		return 0;
+
+	if (uv > MAX_VOLTAGE_RAMP_TPS6236X_UV) {
+		pr_err("%s: uv%ld greater than max %d\n", __func__,
+			uv, MAX_VOLTAGE_RAMP_TPS6236X_UV);
+		uv = MAX_VOLTAGE_RAMP_TPS6236X_UV;
+	}
+	return fls(MAX_VOLTAGE_RAMP_TPS6236X_UV / uv) - 1;
+}
+
+static unsigned long tps6236x_vsel_to_uv(const u8 vsel)
+{
+	return (voltage_min +
+		(STEP_SIZE_TPS6236X * (vsel & ~VOLTAGE_PFM_MODE_VAL)));
+}
+
+static u8 tps6236x_uv_to_vsel(unsigned long uv)
+{
+	if (!uv)
+		return 0;
+
+	/* Round off requests to limits */
+	if (uv > voltage_max) {
+		pr_err("%s:Request for overvoltage[%ld] than supported[%ld]\n",
+				__func__, uv, voltage_max);
+		uv = voltage_max;
+	}
+	if (uv < voltage_min) {
+		pr_err("%s:Request for undervoltage[%ld] than supported[%ld]\n",
+				__func__, uv, voltage_min);
+		uv = voltage_min;
+	}
+	return DIV_ROUND_UP(uv - voltage_min, STEP_SIZE_TPS6236X) |
+			VOLTAGE_PFM_MODE_VAL;
+}
+
+static struct omap_voltdm_pmic omap4_mpu_pmic = {
+	.slew_rate		= 8000,
+	.step_size		= STEP_SIZE_TPS6236X,
+	.on_volt		= 1375000,
+	.onlp_volt		= 1375000,
+	.ret_volt		= 830000,
+	.off_volt		= 0,
+	.volt_setup_time	= 0,
+	.vp_erroroffset		= OMAP4_VP_CONFIG_ERROROFFSET,
+	.vp_vstepmin		= OMAP4_VP_VSTEPMIN_VSTEPMIN,
+	.vp_vstepmax		= OMAP4_VP_VSTEPMAX_VSTEPMAX,
+	.vp_vddmin		= OMAP4_VP_MPU_VLIMITTO_VDDMIN,
+	.vp_vddmax		= OMAP4_VP_MPU_VLIMITTO_VDDMAX,
+	.vp_timeout_us		= OMAP4_VP_VLIMITTO_TIMEOUT_US,
+	.i2c_slave_addr		= I2C_TPS6236X_SLAVE_ADDR,
+	.volt_reg_addr		= REG_TPS6236X_SET_0,
+	.cmd_reg_addr		= REG_TPS6236X_SET_0,
+	.i2c_high_speed		= true,
+	.i2c_scll_low		= 0x28,
+	.i2c_scll_high		= 0x2C,
+	.i2c_hscll_low		= 0x0B,
+	.i2c_hscll_high		= 0x00,
+	.vsel_to_uv		= tps6236x_vsel_to_uv,
+	.uv_to_vsel		= tps6236x_uv_to_vsel,
+};
+
+/**
+ * omap4_twl_tps62361_enable() - Enable tps chip
+ *
+ * This function enables TPS chip by associating SYSEN signal
+ * to APE resource group of TWL6030.
+ *
+ * Returns 0 on sucess, error is returned if I2C read/write fails.
+ */
+static int __init omap4_twl_tps62361_enable(struct voltagedomain *voltdm)
+{
+	int ret = 0;
+	u8 val;
+
+	/* Dont trust the bootloader. start with max, pm will set to proper */
+	val = voltdm->pmic->uv_to_vsel(voltdm->pmic->vp_vddmax);
+	ret = omap_vc_bypass_send_i2c_msg(voltdm, voltdm->pmic->i2c_slave_addr,
+			default_reg, val);
+
+	/* Setup Ramp */
+	val = tps6236x_ramp_value(voltdm->pmic->slew_rate) <<
+		__ffs(REG_TPS6236X_RAMP_CTRL_RMP_MASK);
+	val &= REG_TPS6236X_RAMP_CTRL_RMP_MASK;
+
+	/* We would like to ramp the voltage asap */
+	val |= REG_TPS6236X_RAMP_CTRL_RAMP_PFM;
+
+	ret = omap_vc_bypass_send_i2c_msg(voltdm, voltdm->pmic->i2c_slave_addr,
+			REG_TPS6236X_RAMP_CTRL, val);
+	if (ret)
+		goto out;
+
+	/* Setup the internal pulls to select if needed */
+	if (pd_vsel0 != -1 || pd_vsel1 != -1) {
+		val = REG_TPS6236X_CTRL_PD_EN;
+		val |= (pd_vsel0) ? 0 : REG_TPS6236X_CTRL_PD_VSEL0;
+		val |= (pd_vsel1) ? 0 : REG_TPS6236X_CTRL_PD_VSEL1;
+		ret = omap_vc_bypass_send_i2c_msg(voltdm,
+					voltdm->pmic->i2c_slave_addr,
+					REG_TPS6236X_CTRL, val);
+		if (ret)
+			goto out;
+	}
+
+	/* Enable thermal shutdown - 0 is enable :) */
+	ret = omap_vc_bypass_send_i2c_msg(voltdm,
+				voltdm->pmic->i2c_slave_addr,
+				REG_TPS6236X_TEMP, 0x0);
+	if (ret)
+		goto out;
+
+	/* if we have to work with TWL */
+#ifdef CONFIG_TWL4030_CORE
+	ret = twl_i2c_read_u8(TWL4030_MODULE_PM_RECEIVER, &val,
+			TWL6030_REG_SYSEN_CFG_GRP);
+	if (ret)
+		goto out;
+
+	val |= TWL6030_BIT_APE_GRP;
+	ret = twl_i2c_write_u8(TWL4030_MODULE_PM_RECEIVER, val,
+			TWL6030_REG_SYSEN_CFG_GRP);
+#endif
+
+out:
+	if (ret)
+		pr_err("%s: Error enabling TPS(%d)\n", __func__, ret);
+
+	return ret;
+}
+
+static __initdata struct omap_pmic_map omap_tps_map[] = {
+	{
+		.name = "mpu",
+		.omap_chip = OMAP_CHIP_INIT(CHIP_IS_OMAP446X),
+		.pmic_data = &omap4_mpu_pmic,
+		.special_action = omap4_twl_tps62361_enable,
+	},
+	/* Terminator */
+	{ .name = NULL,.pmic_data = NULL},
+};
+
+int __init omap_tps6236x_init(void)
+{
+	struct omap_pmic_map *map;
+
+	/* Without registers, I wont proceed */
+	if (default_reg == -1)
+		return -EINVAL;
+
+	map = omap_tps_map;
+
+	/* setup all the pmic's voltage addresses to the default one */
+	while (map->name) {
+		map->pmic_data->volt_reg_addr = default_reg;
+		map->pmic_data->cmd_reg_addr = default_reg;
+		map++;
+	}
+
+	return omap_pmic_register_data(omap_tps_map);
+}
+
+/**
+ * omap_tps6236x_board_setup() - provide the board config for TPS connect
+ * @use_62361:	Do we use TPS62361 variant?
+ * @gpio_vsel0:	If using GPIO to control VSEL0, provide gpio number, else -1
+ * @gpio_vsel1:	If using GPIO to control VSEL1, provide gpio number, else -1
+ * @pull0:	If using GPIO, provide mux mode OMAP_PIN_OFF_OUTPUT_[HIGH|LOW]
+ *		else provide any internal pull required, -1 if unused.
+ * @pull1:	If using GPIO, provide mux mode OMAP_PIN_OFF_OUTPUT_[HIGH|LOW]
+ *		else provide any internal pull required, -1 if unused.
+ *
+ * TPS6236x variants of PMIC can be hooked in numerous combinations on to the
+ * board. Some platforms can choose to hardwire and save on a GPIO for other
+ * uses, while others may hook a single line for GPIO control and may ground
+ * the other line. support these configurations.
+ *
+ * WARNING: for platforms using GPIO, be careful to provide MUX setting
+ * considering OFF mode configuration as well.
+ */
+int __init omap_tps6236x_board_setup(bool use_62361, int gpio_vsel0,
+		int gpio_vsel1, int pull0, int pull1)
+{
+	int r;
+
+	r = _bd_setup("tps6236x_vsel0", gpio_vsel0, &pull0, &pd_vsel0);
+	if (r)
+		goto out;
+	r = _bd_setup("tps6236x_vsel1", gpio_vsel1, &pull1, &pd_vsel1);
+	if (r) {
+		if (gpio_vsel0 != -1)
+			gpio_free(gpio_vsel0);
+		goto out;
+	}
+
+	default_reg = ((pull1 & 0x1) << 1) | (pull0 & 0x1);
+
+	if (use_62361) {
+		voltage_min = MIN_VOLTAGE_TPS62361_UV;
+		voltage_max = MAX_VOLTAGE_TPS62361_UV;
+	} else {
+		voltage_min = MIN_VOLTAGE_TPS62360_62_UV;
+		voltage_max = MAX_VOLTAGE_TPS62360_62_UV;
+	}
+out:
+	return r;
+}