The USB 2.0 specification says that bMaxPower is the maximum power consumption expressed in 2 mA units and the USB 3.0 specification says that it is expressed in 8 mA units. This patch adds a helper function usb_get_max_power() which computes the value based on config & usb_device's speed value. The sysfs interface & the device descriptor dump compute the value on their own. Cc: Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> --- v2..v3: use usb_get_max_power() in sysfs code. drivers/usb/core/devices.c | 13 ++++++++++--- drivers/usb/core/generic.c | 2 +- drivers/usb/core/hub.c | 2 +- drivers/usb/core/message.c | 2 +- drivers/usb/core/sysfs.c | 31 ++++++++++++++++++++++--------- drivers/usb/core/usb.h | 9 +++++++++ 6 files changed, 44 insertions(+), 15 deletions(-) diff --git a/drivers/usb/core/devices.c b/drivers/usb/core/devices.c index cbacea9..e33224e 100644 --- a/drivers/usb/core/devices.c +++ b/drivers/usb/core/devices.c @@ -316,17 +316,23 @@ static char *usb_dump_iad_descriptor(char *start, char *end, */ static char *usb_dump_config_descriptor(char *start, char *end, const struct usb_config_descriptor *desc, - int active) + int active, int speed) { + int mul; + if (start > end) return start; + if (speed == USB_SPEED_SUPER) + mul = 8; + else + mul = 2; start += sprintf(start, format_config, /* mark active/actual/current cfg. */ active ? '*' : ' ', desc->bNumInterfaces, desc->bConfigurationValue, desc->bmAttributes, - desc->bMaxPower * 2); + desc->bMaxPower * mul); return start; } @@ -342,7 +348,8 @@ static char *usb_dump_config(int speed, char *start, char *end, if (!config) /* getting these some in 2.3.7; none in 2.3.6 */ return start + sprintf(start, "(null Cfg. desc.)\n"); - start = usb_dump_config_descriptor(start, end, &config->desc, active); + start = usb_dump_config_descriptor(start, end, &config->desc, active, + speed); for (i = 0; i < USB_MAXIADS; i++) { if (config->intf_assoc[i] == NULL) break; diff --git a/drivers/usb/core/generic.c b/drivers/usb/core/generic.c index eff2010..271e761 100644 --- a/drivers/usb/core/generic.c +++ b/drivers/usb/core/generic.c @@ -100,7 +100,7 @@ int usb_choose_configuration(struct usb_device *udev) */ /* Rule out configs that draw too much bus current */ - if (c->desc.bMaxPower * 2 > udev->bus_mA) { + if (usb_get_max_power(udev, c) > udev->bus_mA) { insufficient_power++; continue; } diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index a815fd2..4735425 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -4152,7 +4152,7 @@ hub_power_remaining (struct usb_hub *hub) /* Unconfigured devices may not use more than 100mA, * or 8mA for OTG ports */ if (udev->actconfig) - delta = udev->actconfig->desc.bMaxPower * 2; + delta = usb_get_max_power(udev, udev->actconfig); else if (port1 != udev->bus->otg_port || hdev->parent) delta = 100; else diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c index 131f736..444d30e 100644 --- a/drivers/usb/core/message.c +++ b/drivers/usb/core/message.c @@ -1751,7 +1751,7 @@ int usb_set_configuration(struct usb_device *dev, int configuration) } } - i = dev->bus_mA - cp->desc.bMaxPower * 2; + i = dev->bus_mA - usb_get_max_power(dev, cp); if (i < 0) dev_warn(&dev->dev, "new config #%d exceeds power " "limit by %dmA\n", diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c index 818e4a0..3f81a3d 100644 --- a/drivers/usb/core/sysfs.c +++ b/drivers/usb/core/sysfs.c @@ -17,7 +17,7 @@ #include "usb.h" /* Active configuration fields */ -#define usb_actconfig_show(field, multiplier, format_string) \ +#define usb_actconfig_show(field, format_string) \ static ssize_t show_##field(struct device *dev, \ struct device_attribute *attr, char *buf) \ { \ @@ -28,18 +28,31 @@ static ssize_t show_##field(struct device *dev, \ actconfig = udev->actconfig; \ if (actconfig) \ return sprintf(buf, format_string, \ - actconfig->desc.field * multiplier); \ + actconfig->desc.field); \ else \ return 0; \ } \ -#define usb_actconfig_attr(field, multiplier, format_string) \ -usb_actconfig_show(field, multiplier, format_string) \ -static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL); +#define usb_actconfig_attr(field, format_string) \ + usb_actconfig_show(field, format_string) \ + static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL); + +usb_actconfig_attr(bNumInterfaces, "%2d\n") +usb_actconfig_attr(bmAttributes, "%2x\n") -usb_actconfig_attr(bNumInterfaces, 1, "%2d\n") -usb_actconfig_attr(bmAttributes, 1, "%2x\n") -usb_actconfig_attr(bMaxPower, 2, "%3dmA\n") +static ssize_t show_bMaxPower(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct usb_device *udev; + struct usb_host_config *actconfig; + + udev = to_usb_device(dev); + actconfig = udev->actconfig; + if (!actconfig) + return 0; + return sprintf(buf, "%dmA\n", usb_get_max_power(udev, actconfig)); +} +static DEVICE_ATTR(bMaxPower, S_IRUGO, show_bMaxPower, NULL); static ssize_t show_configuration_string(struct device *dev, struct device_attribute *attr, char *buf) @@ -56,7 +69,7 @@ static ssize_t show_configuration_string(struct device *dev, static DEVICE_ATTR(configuration, S_IRUGO, show_configuration_string, NULL); /* configuration value is always present, and r/w */ -usb_actconfig_show(bConfigurationValue, 1, "%u\n"); +usb_actconfig_show(bConfigurationValue, "%u\n"); static ssize_t set_bConfigurationValue(struct device *dev, struct device_attribute *attr, diff --git a/drivers/usb/core/usb.h b/drivers/usb/core/usb.h index 1c528c1..fb7d8fc 100644 --- a/drivers/usb/core/usb.h +++ b/drivers/usb/core/usb.h @@ -38,6 +38,15 @@ extern char *usb_cache_string(struct usb_device *udev, int index); extern int usb_set_configuration(struct usb_device *dev, int configuration); extern int usb_choose_configuration(struct usb_device *udev); +static inline unsigned usb_get_max_power(struct usb_device *udev, + struct usb_host_config *c) +{ + /* SuperSpeed power is in 8 mA units; others are in 2 mA units */ + unsigned mul = (udev->speed == USB_SPEED_SUPER ? 8 : 2); + + return c->desc.bMaxPower * mul; +} + extern void usb_kick_khubd(struct usb_device *dev); extern int usb_match_one_id_intf(struct usb_device *dev, struct usb_host_interface *intf, -- 1.7.10.4 -- 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