[PATCH 2/2] staging: wilc1000: look for rtc_clk clock

[<Eugen.Hristev@xxxxxxxxxxxxx>]

From: Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx>

If rtc_clk is provided from DT, use it and enable it.
This is optional.
The signal may be hardcoded and no need to be requested,
but if DT provides it, use it.

Signed-off-by: Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx>
---
 drivers/staging/wilc1000/wilc_sdio.c          | 14 ++++++++++++++
 drivers/staging/wilc1000/wilc_wfi_netdevice.h |  1 +
 2 files changed, 15 insertions(+)

diff --git a/drivers/staging/wilc1000/wilc_sdio.c b/drivers/staging/wilc1000/wilc_sdio.c
index 4c1c81f..41b69fd 100644
--- a/drivers/staging/wilc1000/wilc_sdio.c
+++ b/drivers/staging/wilc1000/wilc_sdio.c
@@ -4,6 +4,7 @@
  * All rights reserved.
  */
 
+#include <linux/clk.h>
 #include <linux/mmc/sdio_func.h>
 #include <linux/mmc/host.h>
 
@@ -151,6 +152,12 @@ static int wilc_sdio_probe(struct sdio_func *func,
 	wilc->dev = &func->dev;
 	wilc->gpio_irq = gpio;
 
+	wilc->rtc_clk = devm_clk_get(&func->card->dev, "rtc_clk");
+	if (PTR_ERR_OR_ZERO(wilc->rtc_clk) == -EPROBE_DEFER)
+		return -EPROBE_DEFER;
+	else if (!IS_ERR(wilc->rtc_clk))
+		clk_prepare_enable(wilc->rtc_clk);
+
 	dev_info(&func->dev, "Driver Initializing success\n");
 	return 0;
 }
@@ -162,6 +169,10 @@ static void wilc_sdio_remove(struct sdio_func *func)
 	/* free the GPIO in module remove */
 	if (wilc->gpio_irq)
 		gpiod_put(wilc->gpio_irq);
+
+	if (!IS_ERR(wilc->rtc_clk))
+		clk_disable_unprepare(wilc->rtc_clk);
+
 	wilc_netdev_cleanup(wilc);
 }
 
@@ -193,6 +204,9 @@ static int wilc_sdio_suspend(struct device *dev)
 	dev_info(dev, "sdio suspend\n");
 	chip_wakeup(wilc);
 
+	if (!IS_ERR(wilc->rtc_clk))
+		clk_disable_unprepare(wilc->rtc_clk);
+
 	if (!wilc->suspend_event) {
 		wilc_chip_sleep_manually(wilc);
 	} else {
diff --git a/drivers/staging/wilc1000/wilc_wfi_netdevice.h b/drivers/staging/wilc1000/wilc_wfi_netdevice.h
index 1e74a08..d8f3ebe 100644
--- a/drivers/staging/wilc1000/wilc_wfi_netdevice.h
+++ b/drivers/staging/wilc1000/wilc_wfi_netdevice.h
@@ -217,6 +217,7 @@ struct wilc {
 	int io_type;
 	s8 mac_status;
 	struct gpio_desc *gpio_irq;
+	struct clk *rtc_clk;
 	bool initialized;
 	int dev_irq_num;
 	int close;
-- 
2.7.4