diff options
Diffstat (limited to 'drivers/mmc')
| -rw-r--r-- | drivers/mmc/host/sdhci-of-arasan.c | 151 |
1 files changed, 134 insertions, 17 deletions
diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c index e9a9f041e6b0..266799a78c1d 100644 --- a/drivers/mmc/host/sdhci-of-arasan.c +++ b/drivers/mmc/host/sdhci-of-arasan.c @@ -75,10 +75,14 @@ struct sdhci_arasan_soc_ctl_map { * struct sdhci_arasan_clk_data * @sdcardclk_hw: Struct for the clock we might provide to a PHY. * @sdcardclk: Pointer to normal 'struct clock' for sdcardclk_hw. + * @sampleclk_hw: Struct for the clock we might provide to a PHY. + * @sampleclk: Pointer to normal 'struct clock' for sampleclk_hw. */ struct sdhci_arasan_clk_data { struct clk_hw sdcardclk_hw; struct clk *sdcardclk; + struct clk_hw sampleclk_hw; + struct clk *sampleclk; }; /** @@ -557,6 +561,33 @@ static const struct clk_ops arasan_sdcardclk_ops = { }; /** + * sdhci_arasan_sampleclk_recalc_rate - Return the sampling clock rate + * + * Return the current actual rate of the sampling clock. This can be used + * to communicate with out PHY. + * + * @hw: Pointer to the hardware clock structure. + * @parent_rate The parent rate (should be rate of clk_xin). + * Returns the sample clock rate. + */ +static unsigned long sdhci_arasan_sampleclk_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) + +{ + struct sdhci_arasan_clk_data *clk_data = + container_of(hw, struct sdhci_arasan_clk_data, sampleclk_hw); + struct sdhci_arasan_data *sdhci_arasan = + container_of(clk_data, struct sdhci_arasan_data, clk_data); + struct sdhci_host *host = sdhci_arasan->host; + + return host->mmc->actual_clock; +} + +static const struct clk_ops arasan_sampleclk_ops = { + .recalc_rate = sdhci_arasan_sampleclk_recalc_rate, +}; + +/** * sdhci_arasan_update_clockmultiplier - Set corecfg_clockmultiplier * * The corecfg_clockmultiplier is supposed to contain clock multiplier @@ -635,28 +666,21 @@ static void sdhci_arasan_update_baseclkfreq(struct sdhci_host *host) } /** - * sdhci_arasan_register_sdclk - Register the sdclk for a PHY to use + * sdhci_arasan_register_sdcardclk - Register the sdcardclk for a PHY to use * * Some PHY devices need to know what the actual card clock is. In order for * them to find out, we'll provide a clock through the common clock framework * for them to query. * - * Note: without seriously re-architecting SDHCI's clock code and testing on - * all platforms, there's no way to create a totally beautiful clock here - * with all clock ops implemented. Instead, we'll just create a clock that can - * be queried and set the CLK_GET_RATE_NOCACHE attribute to tell common clock - * framework that we're doing things behind its back. This should be sufficient - * to create nice clean device tree bindings and later (if needed) we can try - * re-architecting SDHCI if we see some benefit to it. - * * @sdhci_arasan: Our private data structure. * @clk_xin: Pointer to the functional clock * @dev: Pointer to our struct device. * Returns 0 on success and error value on error */ -static int sdhci_arasan_register_sdclk(struct sdhci_arasan_data *sdhci_arasan, - struct clk *clk_xin, - struct device *dev) +static int +sdhci_arasan_register_sdcardclk(struct sdhci_arasan_data *sdhci_arasan, + struct clk *clk_xin, + struct device *dev) { struct sdhci_arasan_clk_data *clk_data = &sdhci_arasan->clk_data; struct device_node *np = dev->of_node; @@ -664,10 +688,6 @@ static int sdhci_arasan_register_sdclk(struct sdhci_arasan_data *sdhci_arasan, const char *parent_clk_name; int ret; - /* Providing a clock to the PHY is optional; no error if missing */ - if (!of_find_property(np, "#clock-cells", NULL)) - return 0; - ret = of_property_read_string_index(np, "clock-output-names", 0, &sdcardclk_init.name); if (ret) { @@ -689,7 +709,56 @@ static int sdhci_arasan_register_sdclk(struct sdhci_arasan_data *sdhci_arasan, ret = of_clk_add_provider(np, of_clk_src_simple_get, clk_data->sdcardclk); if (ret) - dev_err(dev, "Failed to add clock provider\n"); + dev_err(dev, "Failed to add sdcard clock provider\n"); + + return ret; +} + +/** + * sdhci_arasan_register_sampleclk - Register the sampleclk for a PHY to use + * + * Some PHY devices need to know what the actual card clock is. In order for + * them to find out, we'll provide a clock through the common clock framework + * for them to query. + * + * @sdhci_arasan: Our private data structure. + * @clk_xin: Pointer to the functional clock + * @dev: Pointer to our struct device. + * Returns 0 on success and error value on error + */ +static int +sdhci_arasan_register_sampleclk(struct sdhci_arasan_data *sdhci_arasan, + struct clk *clk_xin, + struct device *dev) +{ + struct sdhci_arasan_clk_data *clk_data = &sdhci_arasan->clk_data; + struct device_node *np = dev->of_node; + struct clk_init_data sampleclk_init; + const char *parent_clk_name; + int ret; + + ret = of_property_read_string_index(np, "clock-output-names", 1, + &sampleclk_init.name); + if (ret) { + dev_err(dev, "DT has #clock-cells but no clock-output-names\n"); + return ret; + } + + parent_clk_name = __clk_get_name(clk_xin); + sampleclk_init.parent_names = &parent_clk_name; + sampleclk_init.num_parents = 1; + sampleclk_init.flags = CLK_GET_RATE_NOCACHE; + sampleclk_init.ops = &arasan_sampleclk_ops; + + clk_data->sampleclk_hw.init = &sampleclk_init; + clk_data->sampleclk = + devm_clk_register(dev, &clk_data->sampleclk_hw); + clk_data->sampleclk_hw.init = NULL; + + ret = of_clk_add_provider(np, of_clk_src_simple_get, + clk_data->sampleclk); + if (ret) + dev_err(dev, "Failed to add sample clock provider\n"); return ret; } @@ -712,6 +781,54 @@ static void sdhci_arasan_unregister_sdclk(struct device *dev) of_clk_del_provider(dev->of_node); } +/** + * sdhci_arasan_register_sdclk - Register the sdcardclk for a PHY to use + * + * Some PHY devices need to know what the actual card clock is. In order for + * them to find out, we'll provide a clock through the common clock framework + * for them to query. + * + * Note: without seriously re-architecting SDHCI's clock code and testing on + * all platforms, there's no way to create a totally beautiful clock here + * with all clock ops implemented. Instead, we'll just create a clock that can + * be queried and set the CLK_GET_RATE_NOCACHE attribute to tell common clock + * framework that we're doing things behind its back. This should be sufficient + * to create nice clean device tree bindings and later (if needed) we can try + * re-architecting SDHCI if we see some benefit to it. + * + * @sdhci_arasan: Our private data structure. + * @clk_xin: Pointer to the functional clock + * @dev: Pointer to our struct device. + * Returns 0 on success and error value on error + */ +static int sdhci_arasan_register_sdclk(struct sdhci_arasan_data *sdhci_arasan, + struct clk *clk_xin, + struct device *dev) +{ + struct device_node *np = dev->of_node; + u32 num_clks = 0; + int ret; + + /* Providing a clock to the PHY is optional; no error if missing */ + if (of_property_read_u32(np, "#clock-cells", &num_clks) < 0) + return 0; + + ret = sdhci_arasan_register_sdcardclk(sdhci_arasan, clk_xin, dev); + if (ret) + return ret; + + if (num_clks) { + ret = sdhci_arasan_register_sampleclk(sdhci_arasan, clk_xin, + dev); + if (ret) { + sdhci_arasan_unregister_sdclk(dev); + return ret; + } + } + + return 0; +} + static int sdhci_arasan_add_host(struct sdhci_arasan_data *sdhci_arasan) { struct sdhci_host *host = sdhci_arasan->host; |