[PATCH v4 4/5] wifi: brcmfmac: Add optional lpo clock enable support

[Jacobe Zang]

WiFi modules often require 32kHz clock to function. Add support to
enable the clock to PCIe driver.

Co-developed-by: Ondrej Jirman <megi@xxxxxx>
Signed-off-by: Ondrej Jirman <megi@xxxxxx>
Signed-off-by: Jacobe Zang <jacobe.zang@xxxxxxxxxx>
---
 drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
index e406e11481a62..4db188a41fd52 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
@@ -6,6 +6,7 @@
 #include <linux/of.h>
 #include <linux/of_irq.h>
 #include <linux/of_net.h>
+#include <linux/clk.h>
 
 #include <defs.h>
 #include "debug.h"
@@ -70,6 +71,7 @@ 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 clk *clk;
 	const char *prop;
 	int irq;
 	int err;
@@ -113,6 +115,13 @@ void brcmf_of_probe(struct device *dev, enum brcmf_bus_type bus_type,
 		of_node_put(root);
 	}
 
+	clk = devm_clk_get_optional_enabled(dev, "lpo");
+	if (IS_ERR(clk))
+	if (clk) {
+		brcmf_dbg(INFO, "enabling 32kHz clock\n");
+		clk_set_rate(clk, 32768);
+	}
+
 	if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
 		return;
 
-- 
2.34.1