From: Jussi Kivilinna Date: Tue, 6 Aug 2013 11:17:42 +0000 (+0300) Subject: i2c: tiny-usb: do not use stack as URB transfer_buffer X-Git-Tag: upstream/snapshot3+hdmi~4430^2~19 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=243ec0909af052d3f420dd6a4d4376e68346d95c;p=platform%2Fadaptation%2Frenesas_rcar%2Frenesas_kernel.git i2c: tiny-usb: do not use stack as URB transfer_buffer Patch fixes i2c-tiny-usb not to use stack as URB transfer_buffer. URB buffers need to be DMA-able, which stack is not. Patch is only compile tested. Signed-off-by: Jussi Kivilinna Signed-off-by: Wolfram Sang --- diff --git a/drivers/i2c/busses/i2c-tiny-usb.c b/drivers/i2c/busses/i2c-tiny-usb.c index 0510636..e7d3b75 100644 --- a/drivers/i2c/busses/i2c-tiny-usb.c +++ b/drivers/i2c/busses/i2c-tiny-usb.c @@ -54,12 +54,16 @@ static int usb_write(struct i2c_adapter *adapter, int cmd, static int usb_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num) { - unsigned char status; + unsigned char *pstatus; struct i2c_msg *pmsg; - int i; + int i, ret; dev_dbg(&adapter->dev, "master xfer %d messages:\n", num); + pstatus = kmalloc(sizeof(*pstatus), GFP_KERNEL); + if (!pstatus) + return -ENOMEM; + for (i = 0 ; i < num ; i++) { int cmd = CMD_I2C_IO; @@ -84,7 +88,8 @@ static int usb_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num) pmsg->buf, pmsg->len) != pmsg->len) { dev_err(&adapter->dev, "failure reading data\n"); - return -EREMOTEIO; + ret = -EREMOTEIO; + goto out; } } else { /* write data */ @@ -93,36 +98,50 @@ static int usb_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num) pmsg->buf, pmsg->len) != pmsg->len) { dev_err(&adapter->dev, "failure writing data\n"); - return -EREMOTEIO; + ret = -EREMOTEIO; + goto out; } } /* read status */ - if (usb_read(adapter, CMD_GET_STATUS, 0, 0, &status, 1) != 1) { + if (usb_read(adapter, CMD_GET_STATUS, 0, 0, pstatus, 1) != 1) { dev_err(&adapter->dev, "failure reading status\n"); - return -EREMOTEIO; + ret = -EREMOTEIO; + goto out; } - dev_dbg(&adapter->dev, " status = %d\n", status); - if (status == STATUS_ADDRESS_NAK) - return -EREMOTEIO; + dev_dbg(&adapter->dev, " status = %d\n", *pstatus); + if (*pstatus == STATUS_ADDRESS_NAK) { + ret = -EREMOTEIO; + goto out; + } } - return i; + ret = i; +out: + kfree(pstatus); + return ret; } static u32 usb_func(struct i2c_adapter *adapter) { - __le32 func; + __le32 *pfunc; + u32 ret; + + pfunc = kmalloc(sizeof(*pfunc), GFP_KERNEL); /* get functionality from adapter */ - if (usb_read(adapter, CMD_GET_FUNC, 0, 0, &func, sizeof(func)) != - sizeof(func)) { + if (!pfunc || usb_read(adapter, CMD_GET_FUNC, 0, 0, pfunc, + sizeof(*pfunc)) != sizeof(*pfunc)) { dev_err(&adapter->dev, "failure reading functionality\n"); - return 0; + ret = 0; + goto out; } - return le32_to_cpu(func); + ret = le32_to_cpup(pfunc); +out: + kfree(pfunc); + return ret; } /* This is the actual algorithm we define */