linux-kernel - [PATCH v2] usb: ohci-at91: use descriptor-based gpio APIs correctly

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Fri, 16 Dec 2016 09:53:53 +0100
From:   Peter Rosin <peda@...ntia.se>
To:     linux-kernel@...r.kernel.org
Cc:     Peter Rosin <peda@...ntia.se>,
        Alan Stern <stern@...land.harvard.edu>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        linux-usb@...r.kernel.org, Wenyou Yang <wenyou.yang@...el.com>
Subject: [PATCH v2] usb: ohci-at91: use descriptor-based gpio APIs correctly

The gpiod_get* function family does not want the -gpio suffix.
Use devm_gpiod_get_index_optional instead of devm_gpiod_get_optional.
The descriptor based APIs handle active high/low automatically.
The vbus-gpios are output, request enable while getting the gpio.
Don't try to get any vbus-gpios for ports outside num-ports.

WTF? Big sigh.

Fixes: 054d4b7b577d ("usb: ohci-at91: Use descriptor-based gpio APIs")
Signed-off-by: Peter Rosin <peda@...ntia.se>
---

Hi!

Ok, I looked again and found one more problem with that garbage patch
(which did not affect me since I have just one port). You might want to
pick this up before v4.10-rc1, it's not nice to regress in the area of
over-current detection...

v1 -> v2 changes:
- use devm_gpiod_get_index_optional instead of devm_gpiod_get_optional

Cheers,
peda

 drivers/usb/host/ohci-at91.c | 24 ++++++++++--------------
 1 file changed, 10 insertions(+), 14 deletions(-)

diff --git a/drivers/usb/host/ohci-at91.c b/drivers/usb/host/ohci-at91.c
index 1b2e09c32c6b..66ec407df2db 100644
--- a/drivers/usb/host/ohci-at91.c
+++ b/drivers/usb/host/ohci-at91.c
@@ -43,7 +43,6 @@ struct at91_usbh_data {
 	struct gpio_desc *overcurrent_pin[AT91_MAX_USBH_PORTS];
 	u8 ports;				/* number of ports on root hub */
 	u8 overcurrent_supported;
-	u8 vbus_pin_active_low[AT91_MAX_USBH_PORTS];
 	u8 overcurrent_status[AT91_MAX_USBH_PORTS];
 	u8 overcurrent_changed[AT91_MAX_USBH_PORTS];
 };
@@ -268,8 +267,7 @@ static void ohci_at91_usb_set_power(struct at91_usbh_data *pdata, int port, int
 	if (!valid_port(port))
 		return;
 
-	gpiod_set_value(pdata->vbus_pin[port],
-			pdata->vbus_pin_active_low[port] ^ enable);
+	gpiod_set_value(pdata->vbus_pin[port], enable);
 }
 
 static int ohci_at91_usb_get_power(struct at91_usbh_data *pdata, int port)
@@ -277,8 +275,7 @@ static int ohci_at91_usb_get_power(struct at91_usbh_data *pdata, int port)
 	if (!valid_port(port))
 		return -EINVAL;
 
-	return gpiod_get_value(pdata->vbus_pin[port]) ^
-	       pdata->vbus_pin_active_low[port];
+	return gpiod_get_value(pdata->vbus_pin[port]);
 }
 
 /*
@@ -535,18 +532,17 @@ static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
 		pdata->ports = ports;
 
 	at91_for_each_port(i) {
-		pdata->vbus_pin[i] = devm_gpiod_get_optional(&pdev->dev,
-							     "atmel,vbus-gpio",
-							     GPIOD_IN);
+		if (i >= pdata->ports)
+			break;
+
+		pdata->vbus_pin[i] =
+			devm_gpiod_get_index_optional(&pdev->dev, "atmel,vbus",
+						      i, GPIOD_OUT_HIGH);
 		if (IS_ERR(pdata->vbus_pin[i])) {
 			err = PTR_ERR(pdata->vbus_pin[i]);
 			dev_err(&pdev->dev, "unable to claim gpio \"vbus\": %d\n", err);
 			continue;
 		}
-
-		pdata->vbus_pin_active_low[i] = gpiod_get_value(pdata->vbus_pin[i]);
-
-		ohci_at91_usb_set_power(pdata, i, 1);
 	}
 
 	at91_for_each_port(i) {
@@ -554,8 +550,8 @@ static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
 			break;
 
 		pdata->overcurrent_pin[i] =
-			devm_gpiod_get_optional(&pdev->dev,
-						"atmel,oc-gpio", GPIOD_IN);
+			devm_gpiod_get_index_optional(&pdev->dev, "atmel,oc",
+						      i, GPIOD_IN);
 		if (IS_ERR(pdata->overcurrent_pin[i])) {
 			err = PTR_ERR(pdata->overcurrent_pin[i]);
 			dev_err(&pdev->dev, "unable to claim gpio \"overcurrent\": %d\n", err);
-- 
2.1.4