[PATCH v6 32/49] serial: ucc_uart: use of_property_read_u32() in ucc_uart_probe()

From: Rasmus Villemoes
Date: Thu Nov 28 2019 - 09:59:08 EST


For this to work correctly on little-endian hosts, don't access the
device-tree properties directly in native endianness, but use the
of_property_read_u32() helper.

Reviewed-by: Timur Tabi <timur@xxxxxxxxxx>
Acked-by: Timur Tabi <timur@xxxxxxxxxx>
Signed-off-by: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
---
drivers/tty/serial/ucc_uart.c | 36 +++++++++++++++--------------------
1 file changed, 15 insertions(+), 21 deletions(-)

diff --git a/drivers/tty/serial/ucc_uart.c b/drivers/tty/serial/ucc_uart.c
index 313697842e24..c055abf4c919 100644
--- a/drivers/tty/serial/ucc_uart.c
+++ b/drivers/tty/serial/ucc_uart.c
@@ -1256,10 +1256,10 @@ static int soft_uart_init(struct platform_device *ofdev)
static int ucc_uart_probe(struct platform_device *ofdev)
{
struct device_node *np = ofdev->dev.of_node;
- const unsigned int *iprop; /* Integer OF properties */
const char *sprop; /* String OF properties */
struct uart_qe_port *qe_port = NULL;
struct resource res;
+ u32 val;
int ret;

/*
@@ -1290,23 +1290,20 @@ static int ucc_uart_probe(struct platform_device *ofdev)

/* Get the UCC number (device ID) */
/* UCCs are numbered 1-7 */
- iprop = of_get_property(np, "cell-index", NULL);
- if (!iprop) {
- iprop = of_get_property(np, "device-id", NULL);
- if (!iprop) {
- dev_err(&ofdev->dev, "UCC is unspecified in "
- "device tree\n");
+ if (of_property_read_u32(np, "cell-index", &val)) {
+ if (of_property_read_u32(np, "device-id", &val)) {
+ dev_err(&ofdev->dev, "UCC is unspecified in device tree\n");
ret = -EINVAL;
goto out_free;
}
}

- if ((*iprop < 1) || (*iprop > UCC_MAX_NUM)) {
- dev_err(&ofdev->dev, "no support for UCC%u\n", *iprop);
+ if (val < 1 || val > UCC_MAX_NUM) {
+ dev_err(&ofdev->dev, "no support for UCC%u\n", val);
ret = -ENODEV;
goto out_free;
}
- qe_port->ucc_num = *iprop - 1;
+ qe_port->ucc_num = val - 1;

/*
* In the future, we should not require the BRG to be specified in the
@@ -1350,13 +1347,12 @@ static int ucc_uart_probe(struct platform_device *ofdev)
}

/* Get the port number, numbered 0-3 */
- iprop = of_get_property(np, "port-number", NULL);
- if (!iprop) {
+ if (of_property_read_u32(np, "port-number", &val)) {
dev_err(&ofdev->dev, "missing port-number in device tree\n");
ret = -EINVAL;
goto out_free;
}
- qe_port->port.line = *iprop;
+ qe_port->port.line = val;
if (qe_port->port.line >= UCC_MAX_UART) {
dev_err(&ofdev->dev, "port-number must be 0-%u\n",
UCC_MAX_UART - 1);
@@ -1386,31 +1382,29 @@ static int ucc_uart_probe(struct platform_device *ofdev)
}
}

- iprop = of_get_property(np, "brg-frequency", NULL);
- if (!iprop) {
+ if (of_property_read_u32(np, "brg-frequency", &val)) {
dev_err(&ofdev->dev,
"missing brg-frequency in device tree\n");
ret = -EINVAL;
goto out_np;
}

- if (*iprop)
- qe_port->port.uartclk = *iprop;
+ if (val)
+ qe_port->port.uartclk = val;
else {
/*
* Older versions of U-Boot do not initialize the brg-frequency
* property, so in this case we assume the BRG frequency is
* half the QE bus frequency.
*/
- iprop = of_get_property(np, "bus-frequency", NULL);
- if (!iprop) {
+ if (of_property_read_u32(np, "bus-frequency", &val)) {
dev_err(&ofdev->dev,
"missing QE bus-frequency in device tree\n");
ret = -EINVAL;
goto out_np;
}
- if (*iprop)
- qe_port->port.uartclk = *iprop / 2;
+ if (val)
+ qe_port->port.uartclk = val / 2;
else {
dev_err(&ofdev->dev,
"invalid QE bus-frequency in device tree\n");
--
2.23.0