Re: [PATCH v2] brcmfmac: Transform compatible string for FW loading

From: Hans de Goede
Date: Mon Jun 29 2020 - 14:38:23 EST


Hi,

On 6/29/20 1:01 PM, matthias.bgg@xxxxxxxxxx wrote:
From: Matthias Brugger <mbrugger@xxxxxxxx>

The driver relies on the compatible string from DT to determine which
FW configuration file it should load. The DTS spec allows for '/' as
part of the compatible string. We change this to '-' so that we will
still be able to load the config file, even when the compatible has a
'/'. This fixes explicitly the firmware loading for
"solidrun,cubox-i/q".

Signed-off-by: Matthias Brugger <mbrugger@xxxxxxxx>

---

Changes in v2:
- use strscpy instead of strncpy (Hans de Goede)
- use strlen(tmp) + 1 for allocation (Hans de Goede, kernel test robot)

.../wireless/broadcom/brcm80211/brcmfmac/of.c | 18 +++++++++++++++---
1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
index b886b56a5e5a..5f0ebaf4d64e 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
@@ -17,7 +17,6 @@ void brcmf_of_probe(struct device *dev, enum brcmf_bus_type bus_type,
{
struct brcmfmac_sdio_pd *sdio = &settings->bus.sdio;
struct device_node *root, *np = dev->of_node;
- struct property *prop;
int irq;
u32 irqf;
u32 val;
@@ -25,8 +24,21 @@ void brcmf_of_probe(struct device *dev, enum brcmf_bus_type bus_type,
/* Set board-type to the first string of the machine compatible prop */
root = of_find_node_by_path("/");
if (root) {
- prop = of_find_property(root, "compatible", NULL);
- settings->board_type = of_prop_next_string(prop, NULL);
+ int i;
+ char *board_type;
+ const char *tmp;
+
+ of_property_read_string_index(root, "compatible", 0, &tmp);
+
+ /* get rid of '/' in the compatible string to be able to find the FW */
+ board_type = devm_kzalloc(dev, strlen(tmp) + 1, GFP_KERNEL);
+ strscpy(board_type, tmp, sizeof(board_type));

sizeof(board_type) == sizeof(char *) == 4 or 8 bytes, which is not what you
want. Maybe store strlen() + 1 in an int len to avoid having to call it 2 times?

+ for (i = 0; i < strlen(board_type); i++) {

And here you probably want to use:

for (i = 0; board_type[i]; i++) {

Rather then calling strlen many times again (in theory each step
through the loop).

Regards,

Hans



+ if (board_type[i] == '/')
+ board_type[i] = '-';
+ }
+ settings->board_type = board_type;
+
of_node_put(root);
}