From 5154e9f126c1d2ee8f5f93d9954f83d82b2d5e64 Mon Sep 17 00:00:00 2001 From: Yoshihiro Shimoda Date: Fri, 8 Jul 2011 14:51:27 +0900 Subject: [PATCH] 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 Signed-off-by: Felipe Balbi --- drivers/usb/gadget/r8a66597-udc.c | 6 +++++- include/linux/usb/r8a66597.h | 3 +++ 2 files changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/usb/gadget/r8a66597-udc.c b/drivers/usb/gadget/r8a66597-udc.c index 4f3f1ce..834a020 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); diff --git a/include/linux/usb/r8a66597.h b/include/linux/usb/r8a66597.h index 26d2167..6e1bfae 100644 --- a/include/linux/usb/r8a66597.h +++ b/include/linux/usb/r8a66597.h @@ -31,6 +31,9 @@ struct r8a66597_platdata { /* This callback can control port power instead of DVSTCTR register. */ void (*port_power)(int port, int power); + /* This parameter is for BUSWAIT */ + u16 buswait; + /* set one = on chip controller, set zero = external controller */ unsigned on_chip:1; -- 2.7.4