usb: max-3421: Fix setting of I/O pins

[ Upstream commit a7efe3fc7cbe27c6eb2c2a3ab612194f8f800f4c ]

To update the I/O pins, the registers are read/modified/written. The
read operation incorrectly always read the first register. Although
wrong, there wasn't any impact as all the output pins are always
written, and the inputs are read only anyway.

Fixes: 2d53139f3162 ("Add support for using a MAX3421E chip as a host driver.")
Signed-off-by: Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz>
Link: https://lore.kernel.org/r/20230207033337.18112-1-mark.tomlinson@alliedtelesis.co.nz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/usb/host/max3421-hcd.c b/drivers/usb/host/max3421-hcd.c
index 352e3ac..19111e8 100644 (file)
--- a/drivers/usb/host/max3421-hcd.c
+++ b/drivers/usb/host/max3421-hcd.c
@@ -1436,7 +1436,7 @@ max3421_spi_thread(void *dev_id)
                         * use spi_wr_buf().
                         */
                        for (i = 0; i < ARRAY_SIZE(max3421_hcd->iopins); ++i) {
-                               u8 val = spi_rd8(hcd, MAX3421_REG_IOPINS1);
+                               u8 val = spi_rd8(hcd, MAX3421_REG_IOPINS1 + i);
 
                                val = ((val & 0xf0) |
                                       (max3421_hcd->iopins[i] & 0x0f));