When switching from gadget to host the driver waits for VBUS
to disappear before doing the actual switch. This waiting is
done by letting hw_wait_reg() poll the OTGSC register. This is
buggy. hw_wait_reg() directly reads the register, but for
reading the OTGSC register hw_read_otgsc() must be used since
this function eventually patches the VBUS status read from extcon
into the raw register value.
To fix this inline the hw_wait_reg() code into its only user and
use the correct function to read the OTGSC register. Since
hw_wait_reg() is unused now remove it.
Signed-off-by: Sascha Hauer <s.ha...@pengutronix.de>
---
drivers/usb/chipidea/ci.h | 3 ---
drivers/usb/chipidea/core.c | 32 --------------------------------
drivers/usb/chipidea/otg.c | 16 ++++++++++++----
3 files changed, 12 insertions(+), 39 deletions(-)
diff --git a/drivers/usb/chipidea/ci.h b/drivers/usb/chipidea/ci.h
index cd41455..05bc4d6 100644
--- a/drivers/usb/chipidea/ci.h
+++ b/drivers/usb/chipidea/ci.h
@@ -428,9 +428,6 @@ int hw_port_test_set(struct ci_hdrc *ci, u8 mode);
u8 hw_port_test_get(struct ci_hdrc *ci);
-int hw_wait_reg(struct ci_hdrc *ci, enum ci_hw_regs reg, u32 mask,
- u32 value, unsigned int timeout_ms);
-
void ci_platform_configure(struct ci_hdrc *ci);
int dbg_create_files(struct ci_hdrc *ci);
diff --git a/drivers/usb/chipidea/core.c b/drivers/usb/chipidea/core.c
index 69426e6..01390e0 100644
--- a/drivers/usb/chipidea/core.c
+++ b/drivers/usb/chipidea/core.c
@@ -516,38 +516,6 @@ int hw_device_reset(struct ci_hdrc *ci)
return 0;
}
-/**
- * hw_wait_reg: wait the register value
- *
- * Sometimes, it needs to wait register value before going on.
- * Eg, when switch to device mode, the vbus value should be lower
- * than OTGSC_BSV before connects to host.
- *
- * @ci: the controller
- * @reg: register index
- * @mask: mast bit
- * @value: the bit value to wait
- * @timeout_ms: timeout in millisecond
- *
- * This function returns an error code if timeout
- */
-int hw_wait_reg(struct ci_hdrc *ci, enum ci_hw_regs reg, u32 mask,
- u32 value, unsigned int timeout_ms)
-{
- unsigned long elapse = jiffies + msecs_to_jiffies(timeout_ms);
-
- while (hw_read(ci, reg, mask) != value) {
- if (time_after(jiffies, elapse)) {
- dev_err(ci->dev, "timeout waiting for %08x in %d\n",
- mask, reg);
- return -ETIMEDOUT;
- }
- msleep(20);
- }
-
- return 0;
-}
-
static irqreturn_t ci_irq(int irq, void *data)
{
struct ci_hdrc *ci = data;
diff --git a/drivers/usb/chipidea/otg.c b/drivers/usb/chipidea/otg.c
index 91989be..d1c4cdf 100644
--- a/drivers/usb/chipidea/otg.c
+++ b/drivers/usb/chipidea/otg.c
@@ -104,7 +104,6 @@ void ci_handle_vbus_change(struct ci_hdrc *ci)
usb_gadget_vbus_disconnect(&ci->gadget);
}
-#define CI_VBUS_STABLE_TIMEOUT_MS 5000
static void ci_handle_id_switch(struct ci_hdrc *ci)
{
enum ci_role role = ci_otg_role(ci);
@@ -117,10 +116,19 @@ static void ci_handle_id_switch(struct ci_hdrc *ci)
ci_role_stop(ci);
- if (role == CI_ROLE_GADGET)
+ if (role == CI_ROLE_GADGET) {
+ unsigned long elapse = jiffies + msecs_to_jiffies(5000);
+
/* wait vbus lower than OTGSC_BSV */
- hw_wait_reg(ci, OP_OTGSC, OTGSC_BSV, 0,
- CI_VBUS_STABLE_TIMEOUT_MS);
+ while (hw_read_otgsc(ci, OTGSC_BSV)) {
+ if (time_after(jiffies, elapse)) {
+ dev_err(ci->dev,
+ "timeout waiting for VBUS disappear\n");
+ break;
+ }
+ msleep(20);
+ }
+ }
ci_role_start(ci, role);
}
--
2.8.1
--
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