Hi Ivan,
On 08/15/2013 10:22 AM, Ivan T. Ivanov wrote:
Hi Georgi,
I have several comments below.
<snip>
Shouldn't we add required clocks here? It looks that some of them
are optional and others mandatory.
Yes, there are various clocks for MMC, SD/SDIO and at least 400mhz must
be provided for the initialization process.
I'll create a device-tree properties for clocks. Thanks!
+#include <linux/types.h>
+#include <linux/input.h>
It seems that this is not required.
Correct, many of them are not required. Thanks!
+#define CORE_PWRCTL_STATUS 0xDC
Please use lower chars for hex numbers
Ok.
+/* This structure keeps information per regulator */
+struct sdhci_msm_reg_data {
+ /* voltage regulator handle */
+ struct regulator *reg;
+ /* regulator name */
+ const char *name;
+ /* voltage level to be set */
+ u32 low_vol_level;
+ u32 high_vol_level;
+ /* Load values for low power and high power mode */
+ u32 lpm_uA;
+ u32 hpm_uA;
+
+ /* is this regulator enabled? */
+ bool is_enabled;
+ /* is this regulator needs to be always on? */
+ bool is_always_on;
+ /* is low power mode setting required for this regulator? */
+ bool lpm_sup;
+};
+
+/*
+ * This structure keeps information for all the
+ * regulators required for a SDCC slot.
+ */
+struct sdhci_msm_slot_reg_data {
+ /* keeps VDD/VCC regulator info */
+ struct sdhci_msm_reg_data *vdd_data;
+ /* keeps VDD IO regulator info */
+ struct sdhci_msm_reg_data *vdd_io_data;
Why not allocate memory at once? I looks like both of
them are required.
Agree. I'll merge all of them into one structure. Thanks!
+ pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata) {
+ dev_err(dev, "failed to allocate memory for platform data\n");
+ goto out;
Just return immediately? Here and bellow.
Ok.
+ /* Get the regulator handle */
+ vreg->reg = devm_regulator_get(dev, vreg->name);
+ if (IS_ERR(vreg->reg)) {
+ ret = PTR_ERR(vreg->reg);
+ pr_err("%s: devm_regulator_get(%s) failed. ret=%d\n",
+ __func__, vreg->name, ret);
__func__ did not bring any additional info. Please remove it.
Ok.
+ goto out;
+ }
+
+ /* sanity check */
+ if (!vreg->high_vol_level || !vreg->hpm_uA) {
+ pr_err("%s: %s invalid constraints specified\n",
+ __func__, vreg->name);
same thing ...
+ ret = -EINVAL;
+ }
+
+out:
+ return ret;
+}
+
+static void sdhci_msm_vreg_deinit_reg(struct sdhci_msm_reg_data *vreg)
+{
+ if (vreg->reg)
If regulator reference has to be checked it should be IS_ERR(vreg->reg).
+ devm_regulator_put(vreg->reg);
There is no need for this with device managed resources.
Ok.
+}
+
+static int sdhci_msm_vreg_set_optimum_mode(struct sdhci_msm_reg_data
+ *vreg, int uA_load)
+{
+ int ret = 0;
+
+ /*
+ * regulators that do not support regulator_set_voltage also
+ * do not support regulator_set_optimum_mode
+ */
+ ret = regulator_set_optimum_mode(vreg->reg, uA_load);
+ if (ret < 0)
+ pr_err
+ ("%s: regulator_set_optimum_mode(%s,uA_load=%d) fail(%d)\n",
+ __func__, vreg->name, uA_load, ret);
+ else
+ /*
+ * regulator_set_optimum_mode() can return non zero
+ * value even for success case.
+ */
+ ret = 0;
+ return ret;
Is it really necessary to have function wrapper?
Will clean it.
+/* This init function should be called only once for each SDHC slot */
+static int sdhci_msm_vreg_init(struct device *dev,
+ struct sdhci_msm_pltfm_data *pdata, bool is_init)
+{
+ int ret = 0;
+ struct sdhci_msm_slot_reg_data *curr_slot;
+ struct sdhci_msm_reg_data *curr_vdd_reg, *curr_vdd_io_reg;
+
+ curr_slot = pdata->vreg_data;
+ if (!curr_slot)
This could not happen.
+ goto out;
+
+ curr_vdd_reg = curr_slot->vdd_data;
+ curr_vdd_io_reg = curr_slot->vdd_io_data;
+
+ if (!is_init)
+ /* Deregister all regulators from regulator framework */
+ goto vdd_io_reg_deinit;
+
+ /*
+ * Get the regulator handle from voltage regulator framework
+ * and then try to set the voltage level for the regulator
+ */
+ if (curr_vdd_reg) {
Why you check for this? It is alway true.
+ ret = sdhci_msm_vreg_init_reg(dev, curr_vdd_reg);
+ if (ret)
+ goto out;
+ }
+ if (curr_vdd_io_reg) {
+ ret = sdhci_msm_vreg_init_reg(dev, curr_vdd_io_reg);
+ if (ret)
+ goto vdd_reg_deinit;
+ }
+ ret = sdhci_msm_vreg_reset(pdata);
+ if (ret)
+ dev_err(dev, "vreg reset failed (%d)\n", ret);
+ goto out;
+
+vdd_io_reg_deinit:
+ if (curr_vdd_io_reg)
+ sdhci_msm_vreg_deinit_reg(curr_vdd_io_reg);
+vdd_reg_deinit:
+ if (curr_vdd_reg)
+ sdhci_msm_vreg_deinit_reg(curr_vdd_reg);
+out:
+ return ret;
+}
+
+static int sdhci_msm_set_vdd_io_vol(struct sdhci_msm_pltfm_data *pdata,
+ enum vdd_io_level level,
+ unsigned int voltage_level)
+{
+ int ret = 0;
+ int set_level;
+
+ if (pdata->vreg_data) {
When this will happen?
+ struct sdhci_msm_reg_data *vdd_io_reg =
+ pdata->vreg_data->vdd_io_data;
+
+ if (vdd_io_reg && vdd_io_reg->is_enabled) {
+ switch (level) {
+ case VDD_IO_LOW:
+ set_level = vdd_io_reg->low_vol_level;
+ break;
+ case VDD_IO_HIGH:
+ set_level = vdd_io_reg->high_vol_level;
+ break;
+ case VDD_IO_SET_LEVEL:
+ set_level = voltage_level;
+ break;
+ default:
+ pr_err("%s: invalid argument level = %d",
+ __func__, level);
+ ret = -EINVAL;
+ goto out;
+ }
+ ret = sdhci_msm_vreg_set_voltage(vdd_io_reg,
+ set_level, set_level);
+ }
+ }
+
+out:
+ return ret;
+}
+
+static irqreturn_t sdhci_msm_pwr_irq(int irq, void *data)
+{
+ struct sdhci_msm_host *msm_host = (struct sdhci_msm_host *)data;
+ u8 irq_status = 0;
+ u8 irq_ack = 0;
+ int ret = 0;
+
+ irq_status = readb_relaxed(msm_host->core_mem + CORE_PWRCTL_STATUS);
+ pr_debug("%s: Received IRQ(%d), status=0x%x\n",
+ mmc_hostname(msm_host->mmc), irq, irq_status);
+
+ /* Clear the interrupt */
+ writeb_relaxed(irq_status, (msm_host->core_mem + CORE_PWRCTL_CLEAR));
+ /*
+ * SDHC has core_mem and hc_mem device memory and these memory
+ * addresses do not fall within 1KB region. Hence, any update to
+ * core_mem address space would require an mb() to ensure this gets
+ * completed before its next update to registers within hc_mem.
+ */
+ mb();
+
+ /* Handle BUS ON/OFF */
+ if (irq_status & (CORE_PWRCTL_BUS_ON | CORE_PWRCTL_BUS_OFF)) {
+ bool flag = (irq_status & CORE_PWRCTL_BUS_ON) ? 1 : 0;
+ ret = sdhci_msm_setup_vreg(msm_host->pdata, flag, false);
+ if (ret)
+ irq_ack |= CORE_PWRCTL_BUS_FAIL;
+ else
+ irq_ack |= CORE_PWRCTL_BUS_SUCCESS;
+ goto out;
goto out?
+ }
+ /* Handle IO LOW/HIGH */
+ if (irq_status & (CORE_PWRCTL_IO_LOW | CORE_PWRCTL_IO_HIGH)) {
+ /* Switch voltage */
+ int io_status = (irq_status & CORE_PWRCTL_IO_LOW) ?
+ VDD_IO_LOW : VDD_IO_HIGH;
+ ret = sdhci_msm_set_vdd_io_vol(msm_host->pdata, io_status, 0);
+ if (ret)
+ irq_ack |= CORE_PWRCTL_IO_FAIL;
+ else
+ irq_ack |= CORE_PWRCTL_IO_SUCCESS;
+ goto out;
Ditto.
+ }
+
+out:
+ /* ACK status to the core */
+ writeb_relaxed(irq_ack, (msm_host->core_mem + CORE_PWRCTL_CTL));
+ /*
+ * SDHC has core_mem and hc_mem device memory and these memory
+ * addresses do not fall within 1KB region. Hence, any update to
+ * core_mem address space would require an mb() to ensure this gets
+ * completed before its next update to registers within hc_mem.
+ */
+ mb();
+
+ pr_debug("%s: Handled IRQ(%d), ret=%d, ack=0x%x\n",
+ mmc_hostname(msm_host->mmc), irq, ret, irq_ack);
+ return IRQ_HANDLED;
+}
+
+/* This function returns the max. current supported by VDD rail in mA */
+static unsigned int sdhci_msm_get_vreg_vdd_max_current(struct sdhci_msm_host
+ *host)
+{
+ struct sdhci_msm_slot_reg_data *curr_slot = host->pdata->vreg_data;
+ if (!curr_slot)
+ return 0;
+ if (curr_slot->vdd_data)
+ return curr_slot->vdd_data->hpm_uA / 1000;
+ else
Is this possible?
+ return 0;
+}
+
+static const struct of_device_id sdhci_msm_dt_match[] = {
+ {.compatible = "qcom,sdhci-msm"},
+};
+
+MODULE_DEVICE_TABLE(of, sdhci_msm_dt_match);
+
+static int sdhci_msm_probe(struct platform_device *pdev)
+{
+ const struct of_device_id *match;
+ struct sdhci_host *host;
+ struct sdhci_pltfm_host *pltfm_host;
+ struct sdhci_msm_host *msm_host;
+ struct resource *core_memres = NULL;
+ int ret = 0, dead = 0;
+ struct pinctrl *pinctrl;
+
+ match = of_match_device(of_match_ptr(sdhci_msm_dt_match), &pdev->dev);
+ if (!match)
Is this possible?
No, it's not needed. Will remove it.
+ return -ENXIO;
+
+ msm_host = devm_kzalloc(&pdev->dev, sizeof(struct sdhci_msm_host),
+ GFP_KERNEL);
+ if (!msm_host) {
+ ret = -ENOMEM;
Just return -ENOMEM?
Ok.
+ /* Setup Clocks */
+
+ /* Setup SDCC bus voter clock. */
+ msm_host->bus_clk = devm_clk_get(&pdev->dev, "bus_clk");
+ if (!IS_ERR_OR_NULL(msm_host->bus_clk)) {
This should be !IS_ERR(). Is this clock optional?
Yes, it's optional.
+ /* Vote for max. clk rate for max. performance */
+ ret = clk_set_rate(msm_host->bus_clk, INT_MAX);
+ if (ret)
+ goto pltfm_free;
+ ret = clk_prepare_enable(msm_host->bus_clk);
+ if (ret)
+ goto pltfm_free;
+ }
+
+ /* Setup main peripheral bus clock */
+ msm_host->pclk = devm_clk_get(&pdev->dev, "iface_clk");
Is this clock optional?
Yes, its optional.
+
+ host->mmc->max_current_180 =
+ sdhci_msm_get_vreg_vdd_max_current(msm_host);
+ host->mmc->max_current_300 =
+ sdhci_msm_get_vreg_vdd_max_current(msm_host);
+ host->mmc->max_current_330 =
+ sdhci_msm_get_vreg_vdd_max_current(msm_host);
Is it expected that this function to return different result
after each call?
Very unlikely. Will review and change it.
+
+ /* Successful initialization */
+ goto out;
+
+remove_host:
+ dead = (readl_relaxed(host->ioaddr + SDHCI_INT_STATUS) == 0xffffffff);
+ sdhci_remove_host(host, dead);
+vreg_deinit:
+ sdhci_msm_vreg_init(&pdev->dev, msm_host->pdata, false);
+clk_disable:
+ if (!IS_ERR(msm_host->clk))
+ clk_disable_unprepare(msm_host->clk);
+pclk_disable:
+ if (!IS_ERR(msm_host->pclk))
+ clk_disable_unprepare(msm_host->pclk);
+bus_clk_disable:
+ if (!IS_ERR_OR_NULL(msm_host->bus_clk))
+ clk_disable_unprepare(msm_host->bus_clk);
+pltfm_free:
+ sdhci_pltfm_free(pdev);
+out:
+ return ret;
+}
+
+static int sdhci_msm_remove(struct platform_device *pdev)
+{
+ struct sdhci_host *host = platform_get_drvdata(pdev);
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct sdhci_msm_host *msm_host = pltfm_host->priv;
+ int dead = (readl_relaxed(host->ioaddr + SDHCI_INT_STATUS) ==
+ 0xffffffff);
+
+ pr_debug("%s: %s\n", dev_name(&pdev->dev), __func__);
+ sdhci_remove_host(host, dead);
+ sdhci_pltfm_free(pdev);
+ sdhci_msm_vreg_init(&pdev->dev, msm_host->pdata, false);
+ if (!IS_ERR(msm_host->clk))
This is always true.
It should be, otherwise we will fail at probe. I will review the sanity
checks and clean-up where necessary. Thanks!
+ clk_disable_unprepare(msm_host->clk);
+ if (!IS_ERR(msm_host->pclk))
+ clk_disable_unprepare(msm_host->pclk);
+ if (!IS_ERR_OR_NULL(msm_host->bus_clk))
!IS_ERR. And this could happen only if clock is optional.
Correct.
Thank you for detailed review and all the comments!
BR,
Georgi
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