diff options
| author | Joachim Foerster <joachim.foerster@missinglinkelectronics.com> | 2011-10-19 16:18:41 +0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-10-20 00:29:06 +0400 |
| commit | 3a7655fcb210b349111251689d0a56b7250885ea (patch) | |
| tree | b909f3f73d89d1af8807036a3922a19aca41b514 /drivers/usb/host/isp1760-hcd.c | |
| parent | 0f8fd43c42f2cc249943be76a4db0d058c16b6dc (diff) | |
| download | linux-3a7655fcb210b349111251689d0a56b7250885ea.tar.xz | |
usb/isp1760: Allow to optionally trigger low-level chip reset via GPIOLIB.
Properly triggering the reset wire is necessary with the ISP1761 used
on Terasic DE4 Altera-FPGA boards using a NIOS2 processor, for example.
This is an optional implementation for the OF binding only. The other
bindings just pass an invalid GPIO to the isp1760_register() routine.
Example, usage in DTS:
gpios = <&pio_isp1761rst_0 0 1>;
to point to a GPIO controller from within the ISP1761 node: GPIO 0, active low.
Signed-off-by: Joachim Foerster <joachim.foerster@missinglinkelectronics.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/host/isp1760-hcd.c')
| -rw-r--r-- | drivers/usb/host/isp1760-hcd.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/drivers/usb/host/isp1760-hcd.c b/drivers/usb/host/isp1760-hcd.c index 5b08bd743acc..27dfab80ed8f 100644 --- a/drivers/usb/host/isp1760-hcd.c +++ b/drivers/usb/host/isp1760-hcd.c @@ -24,6 +24,7 @@ #include <linux/timer.h> #include <asm/unaligned.h> #include <asm/cacheflush.h> +#include <linux/gpio.h> #include "isp1760-hcd.h" @@ -48,6 +49,8 @@ struct isp1760_hcd { unsigned long reset_done; unsigned long next_statechange; unsigned int devflags; + + int rst_gpio; }; static inline struct isp1760_hcd *hcd_to_priv(struct usb_hcd *hcd) @@ -433,6 +436,18 @@ static int isp1760_hc_setup(struct usb_hcd *hcd) int result; u32 scratch, hwmode; + /* low-level chip reset */ + if (gpio_is_valid(priv->rst_gpio)) { + unsigned int rst_lvl; + + rst_lvl = (priv->devflags & + ISP1760_FLAG_RESET_ACTIVE_HIGH) ? 1 : 0; + + gpio_set_value(priv->rst_gpio, rst_lvl); + mdelay(50); + gpio_set_value(priv->rst_gpio, !rst_lvl); + } + /* Setup HW Mode Control: This assumes a level active-low interrupt */ hwmode = HW_DATA_BUS_32BIT; @@ -2207,6 +2222,7 @@ void deinit_kmem_cache(void) struct usb_hcd *isp1760_register(phys_addr_t res_start, resource_size_t res_len, int irq, unsigned long irqflags, + int rst_gpio, struct device *dev, const char *busname, unsigned int devflags) { @@ -2226,6 +2242,7 @@ struct usb_hcd *isp1760_register(phys_addr_t res_start, resource_size_t res_len, priv = hcd_to_priv(hcd); priv->devflags = devflags; + priv->rst_gpio = rst_gpio; init_memory(priv); hcd->regs = ioremap(res_start, res_len); if (!hcd->regs) { |