On Thu 18 Aug 21:36 PDT 2016, Ritesh Harjani wrote:
> This adds support for sdhc-msm controllers to get supported
> clk-rates from DT. sdhci-msm would need it's own set_clock
> ops to be implemented. For this, supported clk-rates needs
> to be populated in sdhci_msm_pltfm_data.
>
> Signed-off-by: Ritesh Harjani <riteshh@xxxxxxxxxxxxxx>
> ---
> .../devicetree/bindings/mmc/sdhci-msm.txt | 1 +
> drivers/mmc/host/sdhci-msm.c | 71 ++++++++++++++++++++++
> 2 files changed, 72 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/mmc/sdhci-msm.txt b/Documentation/devicetree/bindings/mmc/sdhci-msm.txt
> index 485483a..6a83b38 100644
> --- a/Documentation/devicetree/bindings/mmc/sdhci-msm.txt
> +++ b/Documentation/devicetree/bindings/mmc/sdhci-msm.txt
> @@ -17,6 +17,7 @@ Required properties:
> "iface" - Main peripheral bus clock (PCLK/HCLK - AHB Bus clock) (required)
> "core" - SDC MMC clock (MCLK) (required)
> "bus" - SDCC bus voter clock (optional)
> +- clk-rates: Array of supported GCC clock frequencies for sdhc, Units - Hz.
>
> Example:
>
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
> index 85ddaae..2bf141b 100644
> --- a/drivers/mmc/host/sdhci-msm.c
> +++ b/drivers/mmc/host/sdhci-msm.c
> @@ -74,6 +74,11 @@
> #define CMUX_SHIFT_PHASE_SHIFT 24
> #define CMUX_SHIFT_PHASE_MASK (7 << CMUX_SHIFT_PHASE_SHIFT)
>
> +struct sdhci_msm_pltfm_data {
> + u32 *clk_table;
> + size_t clk_table_sz;
> +};
Rather than calling this "platform data", just call it
sdhci_msm_freq_table and make it:
struct sdhci_msm_freq_table {
size_t num_freqs;
u32 freqs[];
};
> +
> struct sdhci_msm_host {
> struct platform_device *pdev;
> void __iomem *core_mem; /* MSM SDCC mapped address */
> @@ -83,6 +88,7 @@ struct sdhci_msm_host {
> struct clk *bus_clk; /* SDHC bus voter clock */
> struct mmc_host *mmc;
> bool use_14lpp_dll_reset;
> + struct sdhci_msm_pltfm_data *pdata;
> };
>
> /* Platform specific tuning */
> @@ -582,6 +588,67 @@ static const struct sdhci_pltfm_data sdhci_msm_pdata = {
> .ops = &sdhci_msm_ops,
> };
>
> +static int sdhci_msm_dt_get_array(struct device *dev, const char *prop_name,
> + u32 **table, size_t *size)
> +{
> + struct device_node *np = dev->of_node;
> + int count = 0;
> + u32 *arr = NULL;
> + int ret = 0;
> +
> + count = of_property_count_elems_of_size(np, prop_name, sizeof(u32));
> + if (count < 0) {
> + dev_err(dev, "%s: Invalid dt property, err(%d)\n",
> + prop_name, count);
> + ret = count;
> + goto out;
> + }
> +
> + arr = devm_kzalloc(dev, count * sizeof(*arr), GFP_KERNEL);
> + if (!arr) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + ret = of_property_read_u32_array(np, prop_name, arr, count);
> + if (ret) {
> + dev_err(dev, "%s Invalid dt array property, err(%d)\n",
> + prop_name, ret);
> + goto out;
> + }
> + *table = arr;
> + *size = count;
> +out:
> + return ret;
> +}
> +
> +static struct sdhci_msm_pltfm_data *sdhci_msm_populate_pdata(struct device *dev,
> + struct sdhci_msm_host *msm_host)
> +{
> + struct sdhci_msm_pltfm_data *pdata = NULL;
> + size_t table_sz = 0;
> + u32 *table = NULL;
> +
Count of_property_count_elems_of_size() here and then allocate
sizeof(*tbl) + count * sizeof(tbl->freqs[0]) and fill that in, no need
for the two allocations.
> + pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
> + if (!pdata)
> + goto out;
No need for a goto for early errors, just return as you haven't touch
any state yet.
> +
> + if (sdhci_msm_dt_get_array(dev, "clk-rates", &table, &table_sz)) {
> + dev_err(dev, "failed in DT parsing for supported clk-rates\n");
> + goto out;
> + }
> + if (!table || !table_sz) {
A general comment; don't be too defensive in your code. Neither table
nor table_sz should be able to be zero if the above condition fails...
> + dev_err(dev, "Invalid clock table\n");
> + goto out;
> + }
> + pdata->clk_table = table;
> + pdata->clk_table_sz = table_sz;
> +
> + return pdata;
> +out:
> + return NULL;
> +}
> +
> static int sdhci_msm_probe(struct platform_device *pdev)
> {
> struct sdhci_host *host;
> @@ -608,6 +675,10 @@ static int sdhci_msm_probe(struct platform_device *pdev)
>
> sdhci_get_of_property(pdev);
>
> + msm_host->pdata = sdhci_msm_populate_pdata(&pdev->dev, msm_host);
> + if (!msm_host->pdata)
> + goto pltfm_free;
Adding this as a requirement breaks existing platforms/dtbs, you may
force it for 8996 if you can detect that, but you should not change it
for existing platforms.
> +
> /* Setup SDCC bus voter clock. */
> msm_host->bus_clk = devm_clk_get(&pdev->dev, "bus");
> if (!IS_ERR(msm_host->bus_clk)) {
Regards,
Bjorn
--
To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
