[PATCH v2 14/17] phy: qcom-qusb2: Set vbus sw-override signal in device mode

From: Manu Gautam
Date: Wed Sep 27 2017 - 05:05:07 EST


VBUS signal coming from PHY must be asserted in device for
controller to start operation or assert pull-up. For some
platforms where VBUS line is not connected to PHY there is
HS_PHY_CTRL register in QSCRATCH wrapper that can be used
by software to override VBUS signal going to controller.

Signed-off-by: Manu Gautam <mgautam@xxxxxxxxxxxxxx>
---
drivers/phy/qualcomm/phy-qcom-qusb2.c | 39 +++++++++++++++++++++++++++++++++++
1 file changed, 39 insertions(+)

diff --git a/drivers/phy/qualcomm/phy-qcom-qusb2.c b/drivers/phy/qualcomm/phy-qcom-qusb2.c
index bda1f4c..0e9d88b 100644
--- a/drivers/phy/qualcomm/phy-qcom-qusb2.c
+++ b/drivers/phy/qualcomm/phy-qcom-qusb2.c
@@ -68,6 +68,11 @@
#define QUSB2PHY_IMP_CTRL2 0x224
#define QUSB2PHY_CHG_CTRL2 0x23c

+/* QSCRATCH register bits */
+#define QSCRATCH_HS_PHY_CTRL 0x10
+#define UTMI_OTG_VBUS_VALID BIT(20)
+#define SW_SESSVLD_SEL BIT(28)
+
struct qusb2_phy_init_tbl {
unsigned int offset;
unsigned int val;
@@ -211,6 +216,7 @@ struct qusb2_phy_cfg {
*
* @phy: generic phy
* @base: iomapped memory space for qubs2 phy
+ * @qscratch_base: iomapped memory space for qscratch region
*
* @cfg_ahb_clk: AHB2PHY interface clock
* @ref_clk: phy reference clock
@@ -223,10 +229,12 @@ struct qusb2_phy_cfg {
*
* @cfg: phy config data
* @has_se_clk_scheme: indicate if PHY has single-ended ref clock scheme
+ * @mode: indicate current PHY mode of operation e.g. HOST or DEVICE
*/
struct qusb2_phy {
struct phy *phy;
void __iomem *base;
+ void __iomem *qscratch_base;

struct clk *cfg_ahb_clk;
struct clk *ref_clk;
@@ -239,6 +247,7 @@ struct qusb2_phy {

const struct qusb2_phy_cfg *cfg;
bool has_se_clk_scheme;
+ enum phy_mode mode;
};

static inline void qusb2_setbits(void __iomem *base, u32 offset, u32 val)
@@ -307,6 +316,25 @@ static void qusb2_phy_set_tune2_param(struct qusb2_phy *qphy)
qusb2_setbits(qphy->base, QUSB2PHY_PORT_TUNE2, val[0] << 0x4);
}

+static int qusb2_phy_set_mode(struct phy *phy, enum phy_mode mode)
+{
+ struct qusb2_phy *qphy = phy_get_drvdata(phy);
+
+ qphy->mode = mode;
+
+ /* Update VBUS override in qscratch register */
+ if (qphy->qscratch_base) {
+ if (mode == PHY_MODE_USB_DEVICE)
+ qusb2_setbits(qphy->qscratch_base, QSCRATCH_HS_PHY_CTRL,
+ UTMI_OTG_VBUS_VALID | SW_SESSVLD_SEL);
+ else
+ qusb2_clrbits(qphy->qscratch_base, QSCRATCH_HS_PHY_CTRL,
+ UTMI_OTG_VBUS_VALID | SW_SESSVLD_SEL);
+ }
+
+ return 0;
+}
+
static int qusb2_phy_init(struct phy *phy)
{
struct qusb2_phy *qphy = phy_get_drvdata(phy);
@@ -473,6 +501,7 @@ static int qusb2_phy_exit(struct phy *phy)
static const struct phy_ops qusb2_phy_gen_ops = {
.init = qusb2_phy_init,
.exit = qusb2_phy_exit,
+ .set_mode = qusb2_phy_set_mode,
.owner = THIS_MODULE,
};

@@ -507,6 +536,16 @@ static int qusb2_phy_probe(struct platform_device *pdev)
if (IS_ERR(qphy->base))
return PTR_ERR(qphy->base);

+ /* Check if platform uses qscratch wrapper */
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qscratch");
+ if (res) {
+ /* Can't request region as used by other phy and glue drivers */
+ qphy->qscratch_base = devm_ioremap(dev, res->start,
+ resource_size(res));
+ if (IS_ERR(qphy->qscratch_base))
+ return PTR_ERR(qphy->qscratch_base);
+ }
+
qphy->cfg_ahb_clk = devm_clk_get(dev, "cfg_ahb");
if (IS_ERR(qphy->cfg_ahb_clk)) {
ret = PTR_ERR(qphy->cfg_ahb_clk);
--
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