diff options
author | Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> | 2011-07-08 14:51:27 +0900 |
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committer | Felipe Balbi <balbi@ti.com> | 2011-07-08 12:47:42 +0300 |
commit | 5154e9f126c1d2ee8f5f93d9954f83d82b2d5e64 (patch) | |
tree | 337df747ff50d9d154509882b704e2ad3ea07d7f /drivers/usb | |
parent | deafeb24e8a846da8555e68f4bcf651daa8a4ed1 (diff) |
usb: gadget: r8a66597-udc: Make BUSWAIT configurable through platform data
BUSWAIT is a 4-bit-wide value that controls the number of access waits
from the CPU to on-chip USB module. b'0000 inserts 0 wait (2 access
cycles) and b'1111 inserts 15 waits (17 access cycles, hardware
initial value), respectively.
BUSWAIT value depends on peripheral clock frequency supplied to on-chip
of each CPU, hence should be configurable through platform data.
Note that this patch assumes that b'0000 (0 wait, 2 access cycles) is
rerely used and considered as invalid. If valid 'buswait' data is not
provided by platform, initial b'1111 (15 waits, 17 access cycles) will
be applied as a safe default.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Diffstat (limited to 'drivers/usb')
-rw-r--r-- | drivers/usb/gadget/r8a66597-udc.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/usb/gadget/r8a66597-udc.c b/drivers/usb/gadget/r8a66597-udc.c index 4f3f1ce0424..834a0202ae3 100644 --- a/drivers/usb/gadget/r8a66597-udc.c +++ b/drivers/usb/gadget/r8a66597-udc.c @@ -576,7 +576,11 @@ static void init_controller(struct r8a66597 *r8a66597) u16 endian = r8a66597->pdata->endian ? BIGEND : 0; if (r8a66597->pdata->on_chip) { - r8a66597_bset(r8a66597, 0x04, SYSCFG1); + if (r8a66597->pdata->buswait) + r8a66597_write(r8a66597, r8a66597->pdata->buswait, + SYSCFG1); + else + r8a66597_write(r8a66597, 0x0f, SYSCFG1); r8a66597_bset(r8a66597, HSE, SYSCFG0); r8a66597_bclr(r8a66597, USBE, SYSCFG0); |