diff options
Diffstat (limited to 'drivers/mfd')
| -rw-r--r-- | drivers/mfd/sm501.c | 163 |
1 files changed, 128 insertions, 35 deletions
diff --git a/drivers/mfd/sm501.c b/drivers/mfd/sm501.c index 4de8d467762..13bac53db69 100644 --- a/drivers/mfd/sm501.c +++ b/drivers/mfd/sm501.c @@ -48,6 +48,7 @@ struct sm501_devdata { unsigned int pdev_id; unsigned int irq; void __iomem *regs; + unsigned int rev; }; #define MHZ (1000 * 1000) @@ -417,46 +418,108 @@ struct sm501_clock { unsigned long mclk; int divider; int shift; + unsigned int m, n, k; }; +/* sm501_calc_clock + * + * Calculates the nearest discrete clock frequency that + * can be achieved with the specified input clock. + * the maximum divisor is 3 or 5 + */ + +static int sm501_calc_clock(unsigned long freq, + struct sm501_clock *clock, + int max_div, + unsigned long mclk, + long *best_diff) +{ + int ret = 0; + int divider; + int shift; + long diff; + + /* try dividers 1 and 3 for CRT and for panel, + try divider 5 for panel only.*/ + + for (divider = 1; divider <= max_div; divider += 2) { + /* try all 8 shift values.*/ + for (shift = 0; shift < 8; shift++) { + /* Calculate difference to requested clock */ + diff = sm501fb_round_div(mclk, divider << shift) - freq; + if (diff < 0) + diff = -diff; + + /* If it is less than the current, use it */ + if (diff < *best_diff) { + *best_diff = diff; + + clock->mclk = mclk; + clock->divider = divider; + clock->shift = shift; + ret = 1; + } + } + } + + return ret; +} + +/* sm501_calc_pll + * + * Calculates the nearest discrete clock frequency that can be + * achieved using the programmable PLL. + * the maximum divisor is 3 or 5 + */ + +static unsigned long sm501_calc_pll(unsigned long freq, + struct sm501_clock *clock, + int max_div) +{ + unsigned long mclk; + unsigned int m, n, k; + long best_diff = 999999999; + + /* + * The SM502 datasheet doesn't specify the min/max values for M and N. + * N = 1 at least doesn't work in practice. + */ + for (m = 2; m <= 255; m++) { + for (n = 2; n <= 127; n++) { + for (k = 0; k <= 1; k++) { + mclk = (24000000UL * m / n) >> k; + + if (sm501_calc_clock(freq, clock, max_div, + mclk, &best_diff)) { + clock->m = m; + clock->n = n; + clock->k = k; + } + } + } + } + + /* Return best clock. */ + return clock->mclk / (clock->divider << clock->shift); +} + /* sm501_select_clock * - * selects nearest discrete clock frequency the SM501 can achive + * Calculates the nearest discrete clock frequency that can be + * achieved using the 288MHz and 336MHz PLLs. * the maximum divisor is 3 or 5 */ + static unsigned long sm501_select_clock(unsigned long freq, struct sm501_clock *clock, int max_div) { unsigned long mclk; - int divider; - int shift; - long diff; long best_diff = 999999999; /* Try 288MHz and 336MHz clocks. */ for (mclk = 288000000; mclk <= 336000000; mclk += 48000000) { - /* try dividers 1 and 3 for CRT and for panel, - try divider 5 for panel only.*/ - - for (divider = 1; divider <= max_div; divider += 2) { - /* try all 8 shift values.*/ - for (shift = 0; shift < 8; shift++) { - /* Calculate difference to requested clock */ - diff = sm501fb_round_div(mclk, divider << shift) - freq; - if (diff < 0) - diff = -diff; - - /* If it is less than the current, use it */ - if (diff < best_diff) { - best_diff = diff; - - clock->mclk = mclk; - clock->divider = divider; - clock->shift = shift; - } - } - } + sm501_calc_clock(freq, clock, max_div, mclk, &best_diff); } /* Return best clock. */ @@ -478,6 +541,7 @@ unsigned long sm501_set_clock(struct device *dev, unsigned long gate = readl(sm->regs + SM501_CURRENT_GATE); unsigned long clock = readl(sm->regs + SM501_CURRENT_CLOCK); unsigned char reg; + unsigned int pll_reg = 0; unsigned long sm501_freq; /* the actual frequency acheived */ struct sm501_clock to; @@ -492,14 +556,28 @@ unsigned long sm501_set_clock(struct device *dev, * requested frequency the value must be multiplied by * 2. This clock also has an additional pre divisor */ - sm501_freq = (sm501_select_clock(2 * req_freq, &to, 5) / 2); - reg=to.shift & 0x07;/* bottom 3 bits are shift */ - if (to.divider == 3) - reg |= 0x08; /* /3 divider required */ - else if (to.divider == 5) - reg |= 0x10; /* /5 divider required */ - if (to.mclk != 288000000) - reg |= 0x20; /* which mclk pll is source */ + if (sm->rev >= 0xC0) { + /* SM502 -> use the programmable PLL */ + sm501_freq = (sm501_calc_pll(2 * req_freq, + &to, 5) / 2); + reg = to.shift & 0x07;/* bottom 3 bits are shift */ + if (to.divider == 3) + reg |= 0x08; /* /3 divider required */ + else if (to.divider == 5) + reg |= 0x10; /* /5 divider required */ + reg |= 0x40; /* select the programmable PLL */ + pll_reg = 0x20000 | (to.k << 15) | (to.n << 8) | to.m; + } else { + sm501_freq = (sm501_select_clock(2 * req_freq, + &to, 5) / 2); + reg = to.shift & 0x07;/* bottom 3 bits are shift */ + if (to.divider == 3) + reg |= 0x08; /* /3 divider required */ + else if (to.divider == 5) + reg |= 0x10; /* /5 divider required */ + if (to.mclk != 288000000) + reg |= 0x20; /* which mclk pll is source */ + } break; case SM501_CLOCK_V2XCLK: @@ -560,6 +638,10 @@ unsigned long sm501_set_clock(struct device *dev, } writel(mode, sm->regs + SM501_POWER_MODE_CONTROL); + + if (pll_reg) + writel(pll_reg, sm->regs + SM501_PROGRAMMABLE_PLL_CONTROL); + sm501_sync_regs(sm); dev_info(sm->dev, "gate %08lx, clock %08lx, mode %08lx\n", @@ -580,15 +662,24 @@ EXPORT_SYMBOL_GPL(sm501_set_clock); * finds the closest available frequency for a given clock */ -unsigned long sm501_find_clock(int clksrc, +unsigned long sm501_find_clock(struct device *dev, + int clksrc, unsigned long req_freq) { + struct sm501_devdata *sm = dev_get_drvdata(dev); unsigned long sm501_freq; /* the frequency achiveable by the 501 */ struct sm501_clock to; switch (clksrc) { case SM501_CLOCK_P2XCLK: - sm501_freq = (sm501_select_clock(2 * req_freq, &to, 5) / 2); + if (sm->rev >= 0xC0) { + /* SM502 -> use the programmable PLL */ + sm501_freq = (sm501_calc_pll(2 * req_freq, + &to, 5) / 2); + } else { + sm501_freq = (sm501_select_clock(2 * req_freq, + &to, 5) / 2); + } break; case SM501_CLOCK_V2XCLK: @@ -895,6 +986,8 @@ static int sm501_init_dev(struct sm501_devdata *sm) dev_info(sm->dev, "SM501 At %p: Version %08lx, %ld Mb, IRQ %d\n", sm->regs, devid, (unsigned long)mem_avail >> 20, sm->irq); + sm->rev = devid & SM501_DEVICEID_REVMASK; + sm501_dump_gate(sm); ret = device_create_file(sm->dev, &dev_attr_dbg_regs); |