1 files changed, 34 insertions, 4 deletions

diff --git a/drivers/mfd/stm32-lptimer.c b/drivers/mfd/stm32-lptimer.c
index a00f99f36559..123659178cc2 100644
--- a/drivers/mfd/stm32-lptimer.c
+++ b/drivers/mfd/stm32-lptimer.c
@@ -6,9 +6,11 @@
  * Inspired by Benjamin Gaignard's stm32-timers driver
  */
 
+#include <linux/bitfield.h>
 #include <linux/mfd/stm32-lptimer.h>
 #include <linux/module.h>
 #include <linux/of_platform.h>
+#include <linux/platform_device.h>
 
 #define STM32_LPTIM_MAX_REGISTER	0x3fc
 
@@ -47,11 +49,40 @@ static int stm32_lptimer_detect_encoder(struct stm32_lptimer *ddata)
 	return 0;
 }
 
+static int stm32_lptimer_detect_hwcfgr(struct stm32_lptimer *ddata)
+{
+	u32 val;
+	int ret;
+
+	ret = regmap_read(ddata->regmap, STM32_LPTIM_VERR, &ddata->version);
+	if (ret)
+		return ret;
+
+	/* Try to guess parameters from HWCFGR: e.g. encoder mode (STM32MP15) */
+	ret = regmap_read(ddata->regmap, STM32_LPTIM_HWCFGR1, &val);
+	if (ret)
+		return ret;
+
+	/* Fallback to legacy init if HWCFGR isn't present */
+	if (!val)
+		return stm32_lptimer_detect_encoder(ddata);
+
+	ddata->has_encoder = FIELD_GET(STM32_LPTIM_HWCFGR1_ENCODER, val);
+
+	ret = regmap_read(ddata->regmap, STM32_LPTIM_HWCFGR2, &val);
+	if (ret)
+		return ret;
+
+	/* Number of capture/compare channels */
+	ddata->num_cc_chans = FIELD_GET(STM32_LPTIM_HWCFGR2_CHAN_NUM, val);
+
+	return 0;
+}
+
 static int stm32_lptimer_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct stm32_lptimer *ddata;
-	struct resource *res;
 	void __iomem *mmio;
 	int ret;
 
@@ -59,8 +90,7 @@ static int stm32_lptimer_probe(struct platform_device *pdev)
 	if (!ddata)
 		return -ENOMEM;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	mmio = devm_ioremap_resource(dev, res);
+	mmio = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
 	if (IS_ERR(mmio))
 		return PTR_ERR(mmio);
 
@@ -73,7 +103,7 @@ static int stm32_lptimer_probe(struct platform_device *pdev)
 	if (IS_ERR(ddata->clk))
 		return PTR_ERR(ddata->clk);
 
-	ret = stm32_lptimer_detect_encoder(ddata);
+	ret = stm32_lptimer_detect_hwcfgr(ddata);
 	if (ret)
 		return ret;