[PATCH 1/2] usb: dwc3: add a power supply for current control
From: Ray Chi
Date: Mon Feb 22 2021 - 06:54:04 EST
Currently, VBUS draw callback does no action when the
generic PHYs are used. This patch adds an additional
path to control charging current through power supply
interface.
Signed-off-by: Ray Chi <raychi@xxxxxxxxxx>
---
drivers/usb/dwc3/core.c | 15 +++++++++++++++
drivers/usb/dwc3/core.h | 4 ++++
2 files changed, 19 insertions(+)
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index f2448d0a9d39..d15f065849cd 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -1238,6 +1238,8 @@ static void dwc3_get_properties(struct dwc3 *dwc)
u8 rx_max_burst_prd;
u8 tx_thr_num_pkt_prd;
u8 tx_max_burst_prd;
+ const char *usb_psy_name;
+ int ret;
/* default to highest possible threshold */
lpm_nyet_threshold = 0xf;
@@ -1263,6 +1265,13 @@ static void dwc3_get_properties(struct dwc3 *dwc)
else
dwc->sysdev = dwc->dev;
+ ret = device_property_read_string(dev, "usb-psy-name", &usb_psy_name);
+ if (ret >= 0) {
+ dwc->usb_psy = power_supply_get_by_name(usb_psy_name);
+ if (!dwc->usb_psy)
+ dev_err(dev, "couldn't get usb power supply\n");
+ }
+
dwc->has_lpm_erratum = device_property_read_bool(dev,
"snps,has-lpm-erratum");
device_property_read_u8(dev, "snps,lpm-nyet-threshold",
@@ -1619,6 +1628,9 @@ static int dwc3_probe(struct platform_device *pdev)
assert_reset:
reset_control_assert(dwc->reset);
+ if (!dwc->usb_psy)
+ power_supply_put(dwc->usb_psy);
+
return ret;
}
@@ -1641,6 +1653,9 @@ static int dwc3_remove(struct platform_device *pdev)
dwc3_free_event_buffers(dwc);
dwc3_free_scratch_buffers(dwc);
+ if (!dwc->usb_psy)
+ power_supply_put(dwc->usb_psy);
+
return 0;
}
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 052b20d52651..6708fdf358b3 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -30,6 +30,8 @@
#include <linux/phy/phy.h>
+#include <linux/power_supply.h>
+
#define DWC3_MSG_MAX 500
/* Global constants */
@@ -1125,6 +1127,8 @@ struct dwc3 {
struct usb_role_switch *role_sw;
enum usb_dr_mode role_switch_default_mode;
+ struct power_supply *usb_psy;
+
u32 fladj;
u32 irq_gadget;
u32 otg_irq;
--
2.30.0.617.g56c4b15f3c-goog