Re: [PATCH v6 2/2] phy: qualcomm: Add Synopsys High-Speed USB PHY driver

From: mgautam
Date: Wed Dec 19 2018 - 23:03:47 EST


Hi Shawn,

On 2018-12-20 06:31, Shawn Guo wrote:
It adds Synopsys 28nm Femto High-Speed USB PHY driver support, which
is usually paired with Synopsys DWC3 USB controllers on Qualcomm SoCs.

Signed-off-by: Shawn Guo <shawn.guo@xxxxxxxxxx>
---
....

+
+/* PHY register and bit definitions */
+#define PHY_CTRL_COMMON0 0x078
+#define SIDDQ BIT(2)
+#define PHY_IRQ_CMD 0x0d0
+#define PHY_INTR_MASK0 0x0d4
+#define PHY_INTR_CLEAR0 0x0dc
+#define DPDM_MASK 0x1e
+#define DP_1_0 BIT(4)
+#define DP_0_1 BIT(3)
+#define DM_1_0 BIT(2)
+#define DM_0_1 BIT(1)

Can we rename these to something more readable? e.g.:
#define DP_FALL_INT_EN BIT(4)
#define DP_RISE_INT_EN BIT(3)
...

+
+enum hsphy_voltage {
+ VOL_NONE,
+ VOL_MIN,
+ VOL_MAX,
+ VOL_NUM,
+};
+
+enum hsphy_vreg {
+ VDD,
+ VDDA_1P8,
+ VDDA_3P3,
+ VREG_NUM,
+};
+
+struct hsphy_init_seq {
+ int offset;
+ int val;
+ int delay;
+};
+
+struct hsphy_data {
+ const struct hsphy_init_seq *init_seq;
+ unsigned int init_seq_num;
+};
+
+struct hsphy_priv {
nit-pick - indentation for following structure members?

+ void __iomem *base;
+ struct clk_bulk_data *clks;
+ int num_clks;
+ struct reset_control *phy_reset;
+ struct reset_control *por_reset;
+ struct regulator_bulk_data vregs[VREG_NUM];
+ unsigned int voltages[VREG_NUM][VOL_NUM];
+ const struct hsphy_data *data;
+ bool cable_connected;

You can get cable-connected state from "enum phy_mode mode" which
is present in this driver.
E.g. cable_connected is false if mode is neither HOST nor DEVICE.


+ struct extcon_dev *vbus_edev;
+ struct notifier_block vbus_notify;

extcons not needed if you use "mode" for the same purpose.


+ enum phy_mode mode;
+};
+


+
+static int qcom_snps_hsphy_vbus_notifier(struct notifier_block *nb,
+ unsigned long event, void *ptr)
+{
+ struct hsphy_priv *priv = container_of(nb, struct hsphy_priv,
+ vbus_notify);
+ priv->cable_connected = !!event;
+ return 0;
+}
+
+static int qcom_snps_hsphy_power_on(struct phy *phy)

Can you instead merge this power_on function with phy_init?

+{
+ struct hsphy_priv *priv = phy_get_drvdata(phy);
+ int ret;
+
+ if (priv->cable_connected) {

Why distinguish between cable connected vs not-connected?


+ ret = clk_bulk_prepare_enable(priv->num_clks, priv->clks);
+ if (ret)
+ return ret;
+ qcom_snps_hsphy_disable_hv_interrupts(priv);
+ } else {
+ ret = qcom_snps_hsphy_enable_regulators(priv);
+ if (ret)
+ return ret;
+ ret = clk_bulk_prepare_enable(priv->num_clks, priv->clks);
+ if (ret)
+ return ret;
+ qcom_snps_hsphy_exit_retention(priv);
+ }
+
+ return 0;
+}
+
+static int qcom_snps_hsphy_power_off(struct phy *phy)
+{
+ struct hsphy_priv *priv = phy_get_drvdata(phy);
+
+ if (priv->cable_connected) {
+ qcom_snps_hsphy_enable_hv_interrupts(priv);
+ clk_bulk_disable_unprepare(priv->num_clks, priv->clks);
+ } else {
+ qcom_snps_hsphy_enter_retention(priv);
+ clk_bulk_disable_unprepare(priv->num_clks, priv->clks);
+ qcom_snps_hsphy_disable_regulators(priv);
+ }
+
+ return 0;
+}
+



..
+static const struct phy_ops qcom_snps_hsphy_ops = {
+ .init = qcom_snps_hsphy_init,
+ .power_on = qcom_snps_hsphy_power_on,
+ .power_off = qcom_snps_hsphy_power_off,
+ .set_mode = qcom_snps_hsphy_set_mode,

.phy_exit()?
I believe that is needed as dwc3 core driver performs
phy_exit/phy_init across pm_suspend/resume.


+ .owner = THIS_MODULE,
+};
+