OMAP3+: VC: cleanup i2c slave address configuration

- Add an i2c_slave_address field to the omap_vc_channel
- use VC/VP read/modify/write helper instead of open-coding
- remove smps_sa_shift, use __ffs(mask) for shift value
- I2C addresses 10-bit, change size to u16

Special thanks to Shweta Gulati <shweta.gulati@ti.com> for suggesting
the use of __ffs(x) instead of ffs(x) - 1.
Signed-off-by: Kevin Hilman <khilman@ti.com>

arch/arm/mach-omap2/vc.c

@@ -241,11 +241,13 @@ void __init omap_vc_init_channel(struct voltagedomain *voltdm)
 		return;
 	}
 
-	/* Set up the SMPS_SA(i2c slave address in VC */
-	vc_val = voltdm->read(vc->common->smps_sa_reg);
-	vc_val &= ~vc->smps_sa_mask;
-	vc_val |= vdd->pmic_info->i2c_slave_addr << vc->smps_sa_shift;
-	voltdm->write(vc_val, vc->common->smps_sa_reg);
+	/* get PMIC/board specific settings */
+	vc->i2c_slave_addr = vdd->pmic_info->i2c_slave_addr;
+
+	/* Configure the i2c slave address for this VC */
+	voltdm->rmw(vc->smps_sa_mask,
+		    vc->i2c_slave_addr << __ffs(vc->smps_sa_mask),
+		    vc->common->smps_sa_reg);
 
 	/* Setup the VOLRA(pmic reg addr) in VC */
 	vc_val = voltdm->read(vc->common->smps_volra_reg);

arch/arm/mach-omap2/vc.h

@@ -56,21 +56,24 @@ struct omap_vc_common {
 
 /**
  * struct omap_vc_channel - VC per-instance data
+ * @i2c_slave_addr: I2C slave address of PMIC for this VC channel
  * @common: pointer to VC common data for this platform
- * @smps_sa_mask: SA* bitmask in the PRM_VC_SMPS_SA register
+ * @smps_sa_mask: i2c slave address bitmask in the PRM_VC_SMPS_SA register
  * @smps_volra_mask: VOLRA* bitmask in the PRM_VC_VOL_RA register
- * @smps_sa_shift: SA* field shift in the PRM_VC_SMPS_SA register
  * @smps_volra_shift: VOLRA* field shift in the PRM_VC_VOL_RA register
  *
  * XXX It is not necessary to have both a *_mask and a *_shift -
  *     remove one
  */
 struct omap_vc_channel {
+	/* channel state */
+	u16 i2c_slave_addr;
+
+	/* register access data */
 	const struct omap_vc_common *common;
 	u32 smps_sa_mask;
 	u32 smps_volra_mask;
 	u8 cmdval_reg;
-	u8 smps_sa_shift;
 	u8 smps_volra_shift;
 };
 

arch/arm/mach-omap2/vc3xxx_data.c

@@ -47,7 +47,6 @@ static struct omap_vc_common omap3_vc_common = {
 struct omap_vc_channel omap3_vc_mpu = {
 	.common = &omap3_vc_common,
 	.cmdval_reg = OMAP3_PRM_VC_CMD_VAL_0_OFFSET,
-	.smps_sa_shift = OMAP3430_PRM_VC_SMPS_SA_SA0_SHIFT,
 	.smps_sa_mask = OMAP3430_PRM_VC_SMPS_SA_SA0_MASK,
 	.smps_volra_shift = OMAP3430_VOLRA0_SHIFT,
 	.smps_volra_mask = OMAP3430_VOLRA0_MASK,
@@ -56,7 +55,6 @@ struct omap_vc_channel omap3_vc_mpu = {
 struct omap_vc_channel omap3_vc_core = {
 	.common = &omap3_vc_common,
 	.cmdval_reg = OMAP3_PRM_VC_CMD_VAL_1_OFFSET,
-	.smps_sa_shift = OMAP3430_PRM_VC_SMPS_SA_SA1_SHIFT,
 	.smps_sa_mask = OMAP3430_PRM_VC_SMPS_SA_SA1_MASK,
 	.smps_volra_shift = OMAP3430_VOLRA1_SHIFT,
 	.smps_volra_mask = OMAP3430_VOLRA1_MASK,

arch/arm/mach-omap2/vc44xx_data.c

@@ -49,7 +49,6 @@ static const struct omap_vc_common omap4_vc_common = {
 struct omap_vc_channel omap4_vc_mpu = {
 	.common = &omap4_vc_common,
 	.cmdval_reg = OMAP4_PRM_VC_VAL_CMD_VDD_MPU_L_OFFSET,
-	.smps_sa_shift = OMAP4430_SA_VDD_MPU_L_PRM_VC_SMPS_SA_SHIFT,
 	.smps_sa_mask = OMAP4430_SA_VDD_MPU_L_PRM_VC_SMPS_SA_MASK,
 	.smps_volra_shift = OMAP4430_VOLRA_VDD_MPU_L_SHIFT,
 	.smps_volra_mask = OMAP4430_VOLRA_VDD_MPU_L_MASK,
@@ -58,7 +57,6 @@ struct omap_vc_channel omap4_vc_mpu = {
 struct omap_vc_channel omap4_vc_iva = {
 	.common = &omap4_vc_common,
 	.cmdval_reg = OMAP4_PRM_VC_VAL_CMD_VDD_IVA_L_OFFSET,
-	.smps_sa_shift = OMAP4430_SA_VDD_IVA_L_PRM_VC_SMPS_SA_SHIFT,
 	.smps_sa_mask = OMAP4430_SA_VDD_IVA_L_PRM_VC_SMPS_SA_MASK,
 	.smps_volra_shift = OMAP4430_VOLRA_VDD_IVA_L_SHIFT,
 	.smps_volra_mask = OMAP4430_VOLRA_VDD_IVA_L_MASK,
@@ -67,7 +65,6 @@ struct omap_vc_channel omap4_vc_iva = {
 struct omap_vc_channel omap4_vc_core = {
 	.common = &omap4_vc_common,
 	.cmdval_reg = OMAP4_PRM_VC_VAL_CMD_VDD_CORE_L_OFFSET,
-	.smps_sa_shift = OMAP4430_SA_VDD_CORE_L_0_6_SHIFT,
 	.smps_sa_mask = OMAP4430_SA_VDD_CORE_L_0_6_MASK,
 	.smps_volra_shift = OMAP4430_VOLRA_VDD_CORE_L_SHIFT,
 	.smps_volra_mask = OMAP4430_VOLRA_VDD_CORE_L_MASK,

arch/arm/mach-omap2/voltage.h

@@ -102,6 +102,7 @@ struct omap_volt_data {
  * struct omap_volt_pmic_info - PMIC specific data required by voltage driver.
  * @slew_rate:	PMIC slew rate (in uv/us)
  * @step_size:	PMIC voltage step size (in uv)
+ * @i2c_slave_addr: I2C slave address of PMIC
  * @vsel_to_uv:	PMIC API to convert vsel value to actual voltage in uV.
  * @uv_to_vsel:	PMIC API to convert voltage in uV to vsel value.
  * @volt_reg_addr: voltage configuration register address
@@ -115,13 +116,13 @@ struct omap_volt_pmic_info {
 	u32 ret_volt;
 	u32 off_volt;
 	u16 volt_setup_time;
+	u16 i2c_slave_addr;
 	u8 vp_erroroffset;
 	u8 vp_vstepmin;
 	u8 vp_vstepmax;
 	u8 vp_vddmin;
 	u8 vp_vddmax;
 	u8 vp_timeout_us;
-	u8 i2c_slave_addr;
 	u8 volt_reg_addr;
 	u8 cmd_reg_addr;
 	unsigned long (*vsel_to_uv) (const u8 vsel);