>>-----Original Message----- >>From: Manuel, Lesly Arackal >>Sent: Monday, September 27, 2010 9:44 AM >>To: Gopinath, Thara; linux-omap@xxxxxxxxxxxxxxx >>Cc: khilman@xxxxxxxxxxxxxxxxxxx; paul@xxxxxxxxx; Cousson, Benoit; Sripathy, Vishwanath; Sawant, Anand >>Subject: RE: [PATCH v2 03/11] OMAP4: Add the new voltage to vsel calculation formula >> >>Hi Thara, >> >> >>> -----Original Message----- >>> From: linux-omap-owner@xxxxxxxxxxxxxxx [mailto:linux-omap- >>> owner@xxxxxxxxxxxxxxx] On Behalf Of Thara Gopinath >>> Sent: Saturday, September 25, 2010 6:21 PM >>> To: linux-omap@xxxxxxxxxxxxxxx >>> Cc: khilman@xxxxxxxxxxxxxxxxxxx; paul@xxxxxxxxx; b-cousson@xxxxxx; >>> vishwanath.bs@xxxxxx; sawant@xxxxxx; Thara Gopinath >>> Subject: [PATCH v2 03/11] OMAP4: Add the new voltage to vsel calculation >>> formula >>> >>> TWL6030 the power IC used along with OMAP4 in OMAP4 SDPs, >>> blaze boards and panda boards has a different formula >>> from that of TWL4030 for voltage to vsel and >>> vsel to voltage calculation. This patch implements the new >>> formula depending on the PMIC type. >>> >>> Signed-off-by: Thara Gopinath <thara@xxxxxx> >>> --- >>> arch/arm/plat-omap/opp_twl_tps.c | 71 >>> ++++++++++++++++++++++++++++++++++++++ >>> 1 files changed, 71 insertions(+), 0 deletions(-) >>> >>> diff --git a/arch/arm/plat-omap/opp_twl_tps.c b/arch/arm/plat- >>> omap/opp_twl_tps.c >>> index 4448fc5..358b67b 100644 >>> --- a/arch/arm/plat-omap/opp_twl_tps.c >>> +++ b/arch/arm/plat-omap/opp_twl_tps.c >>> @@ -15,9 +15,16 @@ >>> >>> #include <linux/module.h> >>> >>> +#include <linux/i2c/twl.h> >>> + >>> #include <plat/opp_twl_tps.h> >>> #include <plat/voltage.h> >>> >>> +static bool is_offset_valid; >>> +static u8 smps_offset; >>> + >>> +#define REG_SMPS_OFFSET 0xE0 >>> + >>> /** >>> * omap_twl_vsel_to_vdc - convert TWL/TPS VSEL value to microvolts DC >>> * @vsel: TWL/TPS VSEL value to convert >>> @@ -27,6 +34,38 @@ >>> */ >>> unsigned long omap_twl_vsel_to_uv(const u8 vsel) >>> { >>> + if (twl_class_is_6030()) { >>> + /* >>> + * 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, >>0xE0); >>> + is_offset_valid = true; >>> + } >> >>Is it necessary to do the i2c read each time to check the smps_offset? >>OR it can be done one time initially. Hello Lesly, It is not done every time. It is only done the first time omap_twl_vsel_to_uv or omap_twl_uv_to_vsel is called. If is_offset_valid, we do not read the register via i2c interface. Regards Thara -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html