diff options
Diffstat (limited to 'drivers/mfd/twl6040-core.c')
| -rw-r--r-- | drivers/mfd/twl6040-core.c | 128 |
1 files changed, 77 insertions, 51 deletions
diff --git a/drivers/mfd/twl6040-core.c b/drivers/mfd/twl6040-core.c index dda8629..b2d8e51 100644 --- a/drivers/mfd/twl6040-core.c +++ b/drivers/mfd/twl6040-core.c @@ -282,6 +282,7 @@ int twl6040_power(struct twl6040 *twl6040, int on) /* Default PLL configuration after power up */ twl6040->pll = TWL6040_SYSCLK_SEL_LPPLL; twl6040->sysclk = 19200000; + twl6040->mclk = 32768; } else { /* already powered-down */ if (!twl6040->power_count) { @@ -305,6 +306,7 @@ int twl6040_power(struct twl6040 *twl6040, int on) twl6040_power_down(twl6040); } twl6040->sysclk = 0; + twl6040->mclk = 0; } out: @@ -324,23 +326,38 @@ int twl6040_set_pll(struct twl6040 *twl6040, int pll_id, hppllctl = twl6040_reg_read(twl6040, TWL6040_REG_HPPLLCTL); lppllctl = twl6040_reg_read(twl6040, TWL6040_REG_LPPLLCTL); + /* Force full reconfiguration when switching between PLL */ + if (pll_id != twl6040->pll) { + twl6040->sysclk = 0; + twl6040->mclk = 0; + } + switch (pll_id) { case TWL6040_SYSCLK_SEL_LPPLL: /* low-power PLL divider */ - switch (freq_out) { - case 17640000: - lppllctl |= TWL6040_LPLLFIN; - break; - case 19200000: - lppllctl &= ~TWL6040_LPLLFIN; - break; - default: - dev_err(twl6040->dev, - "freq_out %d not supported\n", freq_out); - ret = -EINVAL; - goto pll_out; + /* Change the sysclk configuration only if it has been canged */ + if (twl6040->sysclk != freq_out) { + switch (freq_out) { + case 17640000: + lppllctl |= TWL6040_LPLLFIN; + break; + case 19200000: + lppllctl &= ~TWL6040_LPLLFIN; + break; + default: + dev_err(twl6040->dev, + "freq_out %d not supported\n", + freq_out); + ret = -EINVAL; + goto pll_out; + } + twl6040_reg_write(twl6040, TWL6040_REG_LPPLLCTL, + lppllctl); } - twl6040_reg_write(twl6040, TWL6040_REG_LPPLLCTL, lppllctl); + + /* The PLL in use has not been change, we can exit */ + if (twl6040->pll == pll_id) + break; switch (freq_in) { case 32768: @@ -371,48 +388,56 @@ int twl6040_set_pll(struct twl6040 *twl6040, int pll_id, goto pll_out; } - hppllctl &= ~TWL6040_MCLK_MSK; + if (twl6040->mclk != freq_in) { + hppllctl &= ~TWL6040_MCLK_MSK; + + switch (freq_in) { + case 12000000: + /* PLL enabled, active mode */ + hppllctl |= TWL6040_MCLK_12000KHZ | + TWL6040_HPLLENA; + break; + case 19200000: + /* + * PLL disabled + * (enable PLL if MCLK jitter quality + * doesn't meet specification) + */ + hppllctl |= TWL6040_MCLK_19200KHZ; + break; + case 26000000: + /* PLL enabled, active mode */ + hppllctl |= TWL6040_MCLK_26000KHZ | + TWL6040_HPLLENA; + break; + case 38400000: + /* PLL enabled, active mode */ + hppllctl |= TWL6040_MCLK_38400KHZ | + TWL6040_HPLLENA; + break; + default: + dev_err(twl6040->dev, + "freq_in %d not supported\n", freq_in); + ret = -EINVAL; + goto pll_out; + } - switch (freq_in) { - case 12000000: - /* PLL enabled, active mode */ - hppllctl |= TWL6040_MCLK_12000KHZ | - TWL6040_HPLLENA; - break; - case 19200000: /* - * PLL disabled - * (enable PLL if MCLK jitter quality - * doesn't meet specification) + * enable clock slicer to ensure input waveform is + * square */ - hppllctl |= TWL6040_MCLK_19200KHZ; - break; - case 26000000: - /* PLL enabled, active mode */ - hppllctl |= TWL6040_MCLK_26000KHZ | - TWL6040_HPLLENA; - break; - case 38400000: - /* PLL enabled, active mode */ - hppllctl |= TWL6040_MCLK_38400KHZ | - TWL6040_HPLLENA; - break; - default: - dev_err(twl6040->dev, - "freq_in %d not supported\n", freq_in); - ret = -EINVAL; - goto pll_out; - } + hppllctl |= TWL6040_HPLLSQRENA; - /* enable clock slicer to ensure input waveform is square */ - hppllctl |= TWL6040_HPLLSQRENA; - - twl6040_reg_write(twl6040, TWL6040_REG_HPPLLCTL, hppllctl); - usleep_range(500, 700); - lppllctl |= TWL6040_HPLLSEL; - twl6040_reg_write(twl6040, TWL6040_REG_LPPLLCTL, lppllctl); - lppllctl &= ~TWL6040_LPLLENA; - twl6040_reg_write(twl6040, TWL6040_REG_LPPLLCTL, lppllctl); + twl6040_reg_write(twl6040, TWL6040_REG_HPPLLCTL, + hppllctl); + usleep_range(500, 700); + lppllctl |= TWL6040_HPLLSEL; + twl6040_reg_write(twl6040, TWL6040_REG_LPPLLCTL, + lppllctl); + lppllctl &= ~TWL6040_LPLLENA; + twl6040_reg_write(twl6040, TWL6040_REG_LPPLLCTL, + lppllctl); + } break; default: dev_err(twl6040->dev, "unknown pll id %d\n", pll_id); @@ -421,6 +446,7 @@ int twl6040_set_pll(struct twl6040 *twl6040, int pll_id, } twl6040->sysclk = freq_out; + twl6040->mclk = freq_in; twl6040->pll = pll_id; pll_out: |