This API is used to let the PHY enter/leave low power mode.
Before the controller going to work(at probe/resume), it needs to let
the PHY leave low power mode.
After the controller stopping working(at remove/suspend), it needs to
let the PHY enter low power mode to save power consumption.
Signed-off-by: Peter Chen <peter.chen@xxxxxxxxxxxxx>
---
drivers/usb/chipidea/bits.h | 1 +
drivers/usb/chipidea/core.c | 24 ++++++++++++++++++++++++
2 files changed, 25 insertions(+), 0 deletions(-)
diff --git a/drivers/usb/chipidea/bits.h b/drivers/usb/chipidea/bits.h
index 464584c..a857131 100644
--- a/drivers/usb/chipidea/bits.h
+++ b/drivers/usb/chipidea/bits.h
@@ -48,6 +48,7 @@
#define PORTSC_SUSP BIT(7)
#define PORTSC_HSP BIT(9)
#define PORTSC_PTC (0x0FUL << 16)
+#define PORTSC_PHCD(d) ((d) ? BIT(22) : BIT(23))
/* PTS and PTW for non lpm version only */
#define PORTSC_PTS(d) \
(u32)((((d) & 0x3) << 30) | (((d) & 0x4) ? BIT(25) : 0))
diff --git a/drivers/usb/chipidea/core.c b/drivers/usb/chipidea/core.c
index b20286d..06204b7 100644
--- a/drivers/usb/chipidea/core.c
+++ b/drivers/usb/chipidea/core.c
@@ -172,6 +172,27 @@ u8 hw_port_test_get(struct ci_hdrc *ci)
return hw_read(ci, OP_PORTSC, PORTSC_PTC) >> __ffs(PORTSC_PTC);
}
+/* The PHY enters/leaves low power mode */
+static void ci_hdrc_enter_lpm(struct ci_hdrc *ci, bool enable)
+{
+ enum ci_hw_regs reg = ci->hw_bank.lpm ? OP_DEVLC : OP_PORTSC;
+ bool lpm = !!(hw_read(ci, reg, PORTSC_PHCD(ci->hw_bank.lpm)));
+
+ if (enable && !lpm) {
+ hw_write(ci, reg, PORTSC_PHCD(ci->hw_bank.lpm),
+ PORTSC_PHCD(ci->hw_bank.lpm));
+ } else if (!enable && lpm) {
+ hw_write(ci, reg, PORTSC_PHCD(ci->hw_bank.lpm),
+ 0);
+ /*
+ * The controller needs at least 1ms to reflect
+ * PHY's status, the PHY also needs some time (less
+ * than 1ms) to leave low power mode.
+ */
+ usleep_range(1500, 2000);
+ }
+}
+
static int hw_device_init(struct ci_hdrc *ci, void __iomem *base)
{
u32 reg;
@@ -199,6 +220,8 @@ static int hw_device_init(struct ci_hdrc *ci, void __iomem *base)
if (ci->hw_ep_max > ENDPT_MAX)
return -ENODEV;
+ ci_hdrc_enter_lpm(ci, false);
+
/* Disable all interrupts bits */
hw_write(ci, OP_USBINTR, 0xffffffff, 0);
@@ -648,6 +671,7 @@ static int ci_hdrc_remove(struct platform_device *pdev)
dbg_remove_files(ci);
free_irq(ci->irq, ci);
ci_role_destroy(ci);
+ ci_hdrc_enter_lpm(ci, true);
ci_usb_phy_destroy(ci);
kfree(ci->hw_bank.regmap);
--
1.7.1
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
