Specify voltage in ranges for regulator. Range used is tolerance specified for OPP.
This helps to achieve DVFS with a wider range of regulators. Cc: Kevin Hilman <[email protected]> Cc: Sekhar Nori <[email protected]> Signed-off-by: Afzal Mohammed <[email protected]> --- Hi, Tolerance specified here is that of AM335X, least value of tolerance that I could find so far for OMAP family This applies on top of Kevin Hilman's patch (v2), "cpufreq: OMAP: scale voltage along with frequency" http://www.spinics.net/lists/linux-omap/msg65002.html Regards Afzal drivers/cpufreq/omap-cpufreq.c | 10 +++++++--- 1 files changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/cpufreq/omap-cpufreq.c b/drivers/cpufreq/omap-cpufreq.c index 10b8e23..3cea51b 100644 --- a/drivers/cpufreq/omap-cpufreq.c +++ b/drivers/cpufreq/omap-cpufreq.c @@ -38,6 +38,9 @@ #include <mach/hardware.h> +/* OPP tolerance in percentage */ +#define OPP_TOLERANCE 4 + #ifdef CONFIG_SMP struct lpj_info { unsigned long ref; @@ -81,7 +84,7 @@ static int omap_target(struct cpufreq_policy *policy, int r, ret = 0; struct cpufreq_freqs freqs; struct opp *opp; - unsigned long freq, volt = 0, volt_old = 0; + unsigned long freq, volt = 0, volt_old = 0, tol = 0; if (!freq_table) { dev_err(mpu_dev, "%s: cpu%d: no freq table!\n", __func__, @@ -125,6 +128,7 @@ static int omap_target(struct cpufreq_policy *policy, return -EINVAL; } volt = opp_get_voltage(opp); + tol = volt * OPP_TOLERANCE / 100; volt_old = regulator_get_voltage(mpu_reg); } @@ -134,7 +138,7 @@ static int omap_target(struct cpufreq_policy *policy, /* scaling up? scale voltage before frequency */ if (mpu_reg && (freqs.new > freqs.old)) { - r = regulator_set_voltage(mpu_reg, volt, volt); + r = regulator_set_voltage(mpu_reg, volt - tol, volt + tol); if (r < 0) { dev_warn(mpu_dev, "%s: unable to scale voltage up.\n", __func__); @@ -147,7 +151,7 @@ static int omap_target(struct cpufreq_policy *policy, /* scaling down? scale voltage after frequency */ if (mpu_reg && (freqs.new < freqs.old)) { - r = regulator_set_voltage(mpu_reg, volt, volt); + r = regulator_set_voltage(mpu_reg, volt - tol, volt + tol); if (r < 0) { dev_warn(mpu_dev, "%s: unable to scale voltage down.\n", __func__); -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
