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path: root/drivers/mmc/host/sdhci-s3c.c
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Diffstat (limited to 'drivers/mmc/host/sdhci-s3c.c')
-rw-r--r--drivers/mmc/host/sdhci-s3c.c170
1 files changed, 77 insertions, 93 deletions
diff --git a/drivers/mmc/host/sdhci-s3c.c b/drivers/mmc/host/sdhci-s3c.c
index 6debda952155..d61eb5a70833 100644
--- a/drivers/mmc/host/sdhci-s3c.c
+++ b/drivers/mmc/host/sdhci-s3c.c
@@ -51,12 +51,13 @@ struct sdhci_s3c {
struct platform_device *pdev;
struct resource *ioarea;
struct s3c_sdhci_platdata *pdata;
- unsigned int cur_clk;
+ int cur_clk;
int ext_cd_irq;
int ext_cd_gpio;
struct clk *clk_io;
struct clk *clk_bus[MAX_BUS_CLK];
+ unsigned long clk_rates[MAX_BUS_CLK];
};
/**
@@ -77,32 +78,6 @@ static inline struct sdhci_s3c *to_s3c(struct sdhci_host *host)
}
/**
- * get_curclk - convert ctrl2 register to clock source number
- * @ctrl2: Control2 register value.
- */
-static u32 get_curclk(u32 ctrl2)
-{
- ctrl2 &= S3C_SDHCI_CTRL2_SELBASECLK_MASK;
- ctrl2 >>= S3C_SDHCI_CTRL2_SELBASECLK_SHIFT;
-
- return ctrl2;
-}
-
-static void sdhci_s3c_check_sclk(struct sdhci_host *host)
-{
- struct sdhci_s3c *ourhost = to_s3c(host);
- u32 tmp = readl(host->ioaddr + S3C_SDHCI_CONTROL2);
-
- if (get_curclk(tmp) != ourhost->cur_clk) {
- dev_dbg(&ourhost->pdev->dev, "restored ctrl2 clock setting\n");
-
- tmp &= ~S3C_SDHCI_CTRL2_SELBASECLK_MASK;
- tmp |= ourhost->cur_clk << S3C_SDHCI_CTRL2_SELBASECLK_SHIFT;
- writel(tmp, host->ioaddr + S3C_SDHCI_CONTROL2);
- }
-}
-
-/**
* sdhci_s3c_get_max_clk - callback to get maximum clock frequency.
* @host: The SDHCI host instance.
*
@@ -111,20 +86,11 @@ static void sdhci_s3c_check_sclk(struct sdhci_host *host)
static unsigned int sdhci_s3c_get_max_clk(struct sdhci_host *host)
{
struct sdhci_s3c *ourhost = to_s3c(host);
- struct clk *busclk;
- unsigned int rate, max;
- int clk;
-
- /* note, a reset will reset the clock source */
-
- sdhci_s3c_check_sclk(host);
-
- for (max = 0, clk = 0; clk < MAX_BUS_CLK; clk++) {
- busclk = ourhost->clk_bus[clk];
- if (!busclk)
- continue;
+ unsigned long rate, max = 0;
+ int src;
- rate = clk_get_rate(busclk);
+ for (src = 0; src < MAX_BUS_CLK; src++) {
+ rate = ourhost->clk_rates[src];
if (rate > max)
max = rate;
}
@@ -144,9 +110,9 @@ static unsigned int sdhci_s3c_consider_clock(struct sdhci_s3c *ourhost,
{
unsigned long rate;
struct clk *clksrc = ourhost->clk_bus[src];
- int div;
+ int shift;
- if (!clksrc)
+ if (IS_ERR(clksrc))
return UINT_MAX;
/*
@@ -158,17 +124,24 @@ static unsigned int sdhci_s3c_consider_clock(struct sdhci_s3c *ourhost,
return wanted - rate;
}
- rate = clk_get_rate(clksrc);
+ rate = ourhost->clk_rates[src];
- for (div = 1; div < 256; div *= 2) {
- if ((rate / div) <= wanted)
+ for (shift = 0; shift <= 8; ++shift) {
+ if ((rate >> shift) <= wanted)
break;
}
+ if (shift > 8) {
+ dev_dbg(&ourhost->pdev->dev,
+ "clk %d: rate %ld, min rate %lu > wanted %u\n",
+ src, rate, rate / 256, wanted);
+ return UINT_MAX;
+ }
+
dev_dbg(&ourhost->pdev->dev, "clk %d: rate %ld, want %d, got %ld\n",
- src, rate, wanted, rate / div);
+ src, rate, wanted, rate >> shift);
- return wanted - (rate / div);
+ return wanted - (rate >> shift);
}
/**
@@ -209,20 +182,22 @@ static void sdhci_s3c_set_clock(struct sdhci_host *host, unsigned int clock)
struct clk *clk = ourhost->clk_bus[best_src];
clk_prepare_enable(clk);
- clk_disable_unprepare(ourhost->clk_bus[ourhost->cur_clk]);
-
- /* turn clock off to card before changing clock source */
- writew(0, host->ioaddr + SDHCI_CLOCK_CONTROL);
+ if (ourhost->cur_clk >= 0)
+ clk_disable_unprepare(
+ ourhost->clk_bus[ourhost->cur_clk]);
ourhost->cur_clk = best_src;
- host->max_clk = clk_get_rate(clk);
-
- ctrl = readl(host->ioaddr + S3C_SDHCI_CONTROL2);
- ctrl &= ~S3C_SDHCI_CTRL2_SELBASECLK_MASK;
- ctrl |= best_src << S3C_SDHCI_CTRL2_SELBASECLK_SHIFT;
- writel(ctrl, host->ioaddr + S3C_SDHCI_CONTROL2);
+ host->max_clk = ourhost->clk_rates[best_src];
}
+ /* turn clock off to card before changing clock source */
+ writew(0, host->ioaddr + SDHCI_CLOCK_CONTROL);
+
+ ctrl = readl(host->ioaddr + S3C_SDHCI_CONTROL2);
+ ctrl &= ~S3C_SDHCI_CTRL2_SELBASECLK_MASK;
+ ctrl |= best_src << S3C_SDHCI_CTRL2_SELBASECLK_SHIFT;
+ writel(ctrl, host->ioaddr + S3C_SDHCI_CONTROL2);
+
/* reprogram default hardware configuration */
writel(S3C64XX_SDHCI_CONTROL4_DRIVE_9mA,
host->ioaddr + S3C64XX_SDHCI_CONTROL4);
@@ -254,17 +229,17 @@ static void sdhci_s3c_set_clock(struct sdhci_host *host, unsigned int clock)
static unsigned int sdhci_s3c_get_min_clock(struct sdhci_host *host)
{
struct sdhci_s3c *ourhost = to_s3c(host);
- unsigned int delta, min = UINT_MAX;
+ unsigned long rate, min = ULONG_MAX;
int src;
for (src = 0; src < MAX_BUS_CLK; src++) {
- delta = sdhci_s3c_consider_clock(ourhost, src, 0);
- if (delta == UINT_MAX)
+ rate = ourhost->clk_rates[src] / 256;
+ if (!rate)
continue;
- /* delta is a negative value in this case */
- if (-delta < min)
- min = -delta;
+ if (rate < min)
+ min = rate;
}
+
return min;
}
@@ -272,20 +247,44 @@ static unsigned int sdhci_s3c_get_min_clock(struct sdhci_host *host)
static unsigned int sdhci_cmu_get_max_clock(struct sdhci_host *host)
{
struct sdhci_s3c *ourhost = to_s3c(host);
+ unsigned long rate, max = 0;
+ int src;
- return clk_round_rate(ourhost->clk_bus[ourhost->cur_clk], UINT_MAX);
+ for (src = 0; src < MAX_BUS_CLK; src++) {
+ struct clk *clk;
+
+ clk = ourhost->clk_bus[src];
+ if (IS_ERR(clk))
+ continue;
+
+ rate = clk_round_rate(clk, ULONG_MAX);
+ if (rate > max)
+ max = rate;
+ }
+
+ return max;
}
/* sdhci_cmu_get_min_clock - callback to get minimal supported clock value. */
static unsigned int sdhci_cmu_get_min_clock(struct sdhci_host *host)
{
struct sdhci_s3c *ourhost = to_s3c(host);
+ unsigned long rate, min = ULONG_MAX;
+ int src;
- /*
- * initial clock can be in the frequency range of
- * 100KHz-400KHz, so we set it as max value.
- */
- return clk_round_rate(ourhost->clk_bus[ourhost->cur_clk], 400000);
+ for (src = 0; src < MAX_BUS_CLK; src++) {
+ struct clk *clk;
+
+ clk = ourhost->clk_bus[src];
+ if (IS_ERR(clk))
+ continue;
+
+ rate = clk_round_rate(clk, 0);
+ if (rate < min)
+ min = rate;
+ }
+
+ return min;
}
/* sdhci_cmu_set_clock - callback on clock change.*/
@@ -552,6 +551,7 @@ static int sdhci_s3c_probe(struct platform_device *pdev)
sc->host = host;
sc->pdev = pdev;
sc->pdata = pdata;
+ sc->cur_clk = -1;
platform_set_drvdata(pdev, host);
@@ -566,25 +566,18 @@ static int sdhci_s3c_probe(struct platform_device *pdev)
clk_prepare_enable(sc->clk_io);
for (clks = 0, ptr = 0; ptr < MAX_BUS_CLK; ptr++) {
- struct clk *clk;
char name[14];
snprintf(name, 14, "mmc_busclk.%d", ptr);
- clk = devm_clk_get(dev, name);
- if (IS_ERR(clk))
+ sc->clk_bus[ptr] = devm_clk_get(dev, name);
+ if (IS_ERR(sc->clk_bus[ptr]))
continue;
clks++;
- sc->clk_bus[ptr] = clk;
-
- /*
- * save current clock index to know which clock bus
- * is used later in overriding functions.
- */
- sc->cur_clk = ptr;
+ sc->clk_rates[ptr] = clk_get_rate(sc->clk_bus[ptr]);
dev_info(dev, "clock source %d: %s (%ld Hz)\n",
- ptr, name, clk_get_rate(clk));
+ ptr, name, sc->clk_rates[ptr]);
}
if (clks == 0) {
@@ -593,10 +586,6 @@ static int sdhci_s3c_probe(struct platform_device *pdev)
goto err_no_busclks;
}
-#ifndef CONFIG_PM_RUNTIME
- clk_prepare_enable(sc->clk_bus[sc->cur_clk]);
-#endif
-
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
host->ioaddr = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(host->ioaddr)) {
@@ -709,10 +698,6 @@ static int sdhci_s3c_probe(struct platform_device *pdev)
return 0;
err_req_regs:
-#ifndef CONFIG_PM_RUNTIME
- clk_disable_unprepare(sc->clk_bus[sc->cur_clk]);
-#endif
-
err_no_busclks:
clk_disable_unprepare(sc->clk_io);
@@ -743,9 +728,6 @@ static int sdhci_s3c_remove(struct platform_device *pdev)
pm_runtime_dont_use_autosuspend(&pdev->dev);
pm_runtime_disable(&pdev->dev);
-#ifndef CONFIG_PM_RUNTIME
- clk_disable_unprepare(sc->clk_bus[sc->cur_clk]);
-#endif
clk_disable_unprepare(sc->clk_io);
sdhci_free_host(host);
@@ -779,7 +761,8 @@ static int sdhci_s3c_runtime_suspend(struct device *dev)
ret = sdhci_runtime_suspend_host(host);
- clk_disable_unprepare(ourhost->clk_bus[ourhost->cur_clk]);
+ if (ourhost->cur_clk >= 0)
+ clk_disable_unprepare(ourhost->clk_bus[ourhost->cur_clk]);
clk_disable_unprepare(busclk);
return ret;
}
@@ -792,7 +775,8 @@ static int sdhci_s3c_runtime_resume(struct device *dev)
int ret;
clk_prepare_enable(busclk);
- clk_prepare_enable(ourhost->clk_bus[ourhost->cur_clk]);
+ if (ourhost->cur_clk >= 0)
+ clk_prepare_enable(ourhost->clk_bus[ourhost->cur_clk]);
ret = sdhci_runtime_resume_host(host);
return ret;
}