OMAP4: Register voltage PMIC parameters with the voltage layer

TWL6030 is the power IC used along with OMAP4 in OMAP4 SDPs,
blaze boards and panda boards. This patch registers the OMAP4
PMIC specific information with the voltage layer.
This also involves implementing a different formula for
voltage to vsel and vsel to voltage calculations from
TWL4030.
Signed-off-by: Thara Gopinath <thara@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>

arch/arm/mach-omap2/omap_twl.c

@@ -16,6 +16,7 @@
 #include <linux/err.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
+#include <linux/i2c/twl.h>
 
 #include <plat/voltage.h>
 
@@ -37,6 +38,28 @@
 #define OMAP3630_VP2_VLIMITTO_VDDMIN	0x18
 #define OMAP3630_VP2_VLIMITTO_VDDMAX	0x30
 
+#define OMAP4_SRI2C_SLAVE_ADDR		0x12
+#define OMAP4_VDD_MPU_SR_VOLT_REG	0x55
+#define OMAP4_VDD_IVA_SR_VOLT_REG	0x5B
+#define OMAP4_VDD_CORE_SR_VOLT_REG	0x61
+
+#define OMAP4_VP_CONFIG_ERROROFFSET	0x00
+#define OMAP4_VP_VSTEPMIN_VSTEPMIN	0x01
+#define OMAP4_VP_VSTEPMAX_VSTEPMAX	0x04
+#define OMAP4_VP_VLIMITTO_TIMEOUT_US	200
+
+#define OMAP4_VP_MPU_VLIMITTO_VDDMIN	0xA
+#define OMAP4_VP_MPU_VLIMITTO_VDDMAX	0x39
+#define OMAP4_VP_IVA_VLIMITTO_VDDMIN	0xA
+#define OMAP4_VP_IVA_VLIMITTO_VDDMAX	0x2D
+#define OMAP4_VP_CORE_VLIMITTO_VDDMIN	0xA
+#define OMAP4_VP_CORE_VLIMITTO_VDDMAX	0x28
+
+static bool is_offset_valid;
+static u8 smps_offset;
+
+#define REG_SMPS_OFFSET         0xE0
+
 unsigned long twl4030_vsel_to_uv(const u8 vsel)
 {
 	return (((vsel * 125) + 6000)) * 100;
@@ -47,6 +70,70 @@ u8 twl4030_uv_to_vsel(unsigned long uv)
 	return DIV_ROUND_UP(uv - 600000, 12500);
 }
 
+unsigned long twl6030_vsel_to_uv(const u8 vsel)
+{
+	/*
+	 * In TWL6030 depending on the value of SMPS_OFFSET
+	 * efuse register the voltage range supported in
+	 * standard mode can be either between 0.6V - 1.3V or
+	 * 0.7V - 1.4V. In TWL6030 ES1.0 SMPS_OFFSET efuse
+	 * is programmed to all 0's where as starting from
+	 * TWL6030 ES1.1 the efuse is programmed to 1
+	 */
+	if (!is_offset_valid) {
+		twl_i2c_read_u8(TWL6030_MODULE_ID0, &smps_offset,
+				REG_SMPS_OFFSET);
+		is_offset_valid = true;
+	}
+
+	/*
+	 * There is no specific formula for voltage to vsel
+	 * conversion above 1.3V. There are special hardcoded
+	 * values for voltages above 1.3V. Currently we are
+	 * hardcoding only for 1.35 V which is used for 1GH OPP for
+	 * OMAP4430.
+	 */
+	if (vsel == 0x3A)
+		return 1350000;
+
+	if (smps_offset & 0x8)
+		return ((((vsel - 1) * 125) + 7000)) * 100;
+	else
+		return ((((vsel - 1) * 125) + 6000)) * 100;
+}
+
+u8 twl6030_uv_to_vsel(unsigned long uv)
+{
+	/*
+	 * In TWL6030 depending on the value of SMPS_OFFSET
+	 * efuse register the voltage range supported in
+	 * standard mode can be either between 0.6V - 1.3V or
+	 * 0.7V - 1.4V. In TWL6030 ES1.0 SMPS_OFFSET efuse
+	 * is programmed to all 0's where as starting from
+	 * TWL6030 ES1.1 the efuse is programmed to 1
+	 */
+	if (!is_offset_valid) {
+		twl_i2c_read_u8(TWL6030_MODULE_ID0, &smps_offset,
+				REG_SMPS_OFFSET);
+		is_offset_valid = true;
+	}
+
+	/*
+	 * There is no specific formula for voltage to vsel
+	 * conversion above 1.3V. There are special hardcoded
+	 * values for voltages above 1.3V. Currently we are
+	 * hardcoding only for 1.35 V which is used for 1GH OPP for
+	 * OMAP4430.
+	 */
+	if (uv == 1350000)
+		return 0x3A;
+
+	if (smps_offset & 0x8)
+		return DIV_ROUND_UP(uv - 700000, 12500) + 1;
+	else
+		return DIV_ROUND_UP(uv - 600000, 12500) + 1;
+}
+
 static struct omap_volt_pmic_info omap3_mpu_volt_info = {
 	.slew_rate		= 4000,
 	.step_size		= 12500,
@@ -87,6 +174,85 @@ static struct omap_volt_pmic_info omap3_core_volt_info = {
 	.uv_to_vsel		= twl4030_uv_to_vsel,
 };
 
+static struct omap_volt_pmic_info omap4_mpu_volt_info = {
+	.slew_rate		= 4000,
+	.step_size		= 12500,
+	.on_volt		= 1350000,
+	.onlp_volt		= 1350000,
+	.ret_volt		= 837500,
+	.off_volt		= 600000,
+	.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		= OMAP4_SRI2C_SLAVE_ADDR,
+	.pmic_reg		= OMAP4_VDD_MPU_SR_VOLT_REG,
+	.vsel_to_uv		= twl6030_vsel_to_uv,
+	.uv_to_vsel		= twl6030_uv_to_vsel,
+};
+
+static struct omap_volt_pmic_info omap4_iva_volt_info = {
+	.slew_rate		= 4000,
+	.step_size		= 12500,
+	.on_volt		= 1100000,
+	.onlp_volt		= 1100000,
+	.ret_volt		= 837500,
+	.off_volt		= 600000,
+	.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_IVA_VLIMITTO_VDDMIN,
+	.vp_vddmax		= OMAP4_VP_IVA_VLIMITTO_VDDMAX,
+	.vp_timeout_us		= OMAP4_VP_VLIMITTO_TIMEOUT_US,
+	.i2c_slave_addr		= OMAP4_SRI2C_SLAVE_ADDR,
+	.pmic_reg		= OMAP4_VDD_IVA_SR_VOLT_REG,
+	.vsel_to_uv		= twl6030_vsel_to_uv,
+	.uv_to_vsel		= twl6030_uv_to_vsel,
+};
+
+static struct omap_volt_pmic_info omap4_core_volt_info = {
+	.slew_rate		= 4000,
+	.step_size		= 12500,
+	.on_volt		= 1100000,
+	.onlp_volt		= 1100000,
+	.ret_volt		= 837500,
+	.off_volt		= 600000,
+	.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_CORE_VLIMITTO_VDDMIN,
+	.vp_vddmax		= OMAP4_VP_CORE_VLIMITTO_VDDMAX,
+	.vp_timeout_us		= OMAP4_VP_VLIMITTO_TIMEOUT_US,
+	.i2c_slave_addr		= OMAP4_SRI2C_SLAVE_ADDR,
+	.pmic_reg		= OMAP4_VDD_CORE_SR_VOLT_REG,
+	.vsel_to_uv		= twl6030_vsel_to_uv,
+	.uv_to_vsel		= twl6030_uv_to_vsel,
+};
+
+int __init omap4_twl_init(void)
+{
+	struct voltagedomain *voltdm;
+
+	if (!cpu_is_omap44xx())
+		return -ENODEV;
+
+	voltdm = omap_voltage_domain_lookup("mpu");
+	omap_voltage_register_pmic(voltdm, &omap4_mpu_volt_info);
+
+	voltdm = omap_voltage_domain_lookup("iva");
+	omap_voltage_register_pmic(voltdm, &omap4_iva_volt_info);
+
+	voltdm = omap_voltage_domain_lookup("core");
+	omap_voltage_register_pmic(voltdm, &omap4_core_volt_info);
+
+	return 0;
+}
+
 int __init omap3_twl_init(void)
 {
 	struct voltagedomain *voltdm;

arch/arm/mach-omap2/pm.c

@@ -240,6 +240,7 @@ static int __init omap2_common_pm_late_init(void)
 {
 	/* Init the OMAP TWL parameters */
 	omap3_twl_init();
+	omap4_twl_init();
 
 	/* Init the voltage layer */
 	omap_voltage_late_init();

arch/arm/mach-omap2/pm.h

@@ -126,11 +126,16 @@ static inline void omap_enable_smartreflex_on_init(void) {}
 
 #ifdef CONFIG_TWL4030_CORE
 extern int omap3_twl_init(void);
+extern int omap4_twl_init(void);
 #else
 static inline int omap3_twl_init(void)
 {
 	return -EINVAL;
 }
+static inline int omap4_twl_init(void)
+{
+	return -EINVAL;
+}
 #endif
 
 #endif