[PATCH 1/3] mfd: tqmx86: do not access I2C_DETECT register through io_base

From: Matthias Schiffer
Date: Thu Feb 16 2023 - 09:35:02 EST


The I2C_DETECT register is at IO port 0x1a7, which is outside the range
passed to devm_ioport_map() for io_base, and was only working because
there aren't actually any bounds checks for IO port accesses.

Extending the range does not seem like a good solution here, as it would
then conflict with the IO resource assigned to the I2C controller. As
this is just a one-off access during probe, use a simple inb() instead.

While we're at it, drop the unused define TQMX86_REG_I2C_INT_EN.

Fixes: 2f17dd34ffed ("mfd: tqmx86: IO controller with I2C, Wachdog and GPIO")
Signed-off-by: Matthias Schiffer <matthias.schiffer@xxxxxxxxxxxxxxx>
---
drivers/mfd/tqmx86.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/mfd/tqmx86.c b/drivers/mfd/tqmx86.c
index 7ae906ff8e353..8dcbdafa88f4f 100644
--- a/drivers/mfd/tqmx86.c
+++ b/drivers/mfd/tqmx86.c
@@ -49,9 +49,8 @@
#define TQMX86_REG_IO_EXT_INT_MASK 0x3
#define TQMX86_REG_IO_EXT_INT_GPIO_SHIFT 4

-#define TQMX86_REG_I2C_DETECT 0x47
+#define TQMX86_REG_I2C_DETECT 0x1a7
#define TQMX86_REG_I2C_DETECT_SOFT 0xa5
-#define TQMX86_REG_I2C_INT_EN 0x49

static uint gpio_irq;
module_param(gpio_irq, uint, 0);
@@ -213,7 +212,7 @@ static int tqmx86_probe(struct platform_device *pdev)
"Found %s - Board ID %d, PCB Revision %d, PLD Revision %d\n",
board_name, board_id, rev >> 4, rev & 0xf);

- i2c_det = ioread8(io_base + TQMX86_REG_I2C_DETECT);
+ i2c_det = inb(TQMX86_REG_I2C_DETECT);

if (gpio_irq_cfg) {
io_ext_int_val =
--
2.34.1