spi: stm32-ospi: Make usage of reset_control_acquire/release() API

As ospi reset is consumed by both OMM and OSPI drivers, use the reset
acquire/release mechanism which ensure exclusive reset usage.

This avoid to call reset_control_get/put() in OMM driver each time
we need to reset OSPI children and guarantee the reset line stays
deasserted.

During resume, OMM driver takes temporarily control of reset.

Fixes: 79b8a70 ("spi: stm32: Add OSPI driver")
Signed-off-by: Patrice Chotard <[email protected]>
Reviewed-by: Philipp Zabel <[email protected]>
Link: https://patch.msgid.link/20250609-b4-upstream_ospi_reset_update-v6-1-5b602b567e8a@foss.st.com
Signed-off-by: Mark Brown <[email protected]>

Author: Patrice Chotard

drivers/spi/spi-stm32-ospi.c

@@ -804,7 +804,7 @@ static int stm32_ospi_get_resources(struct platform_device *pdev)
 		return ret;
 	}
 
-	ospi->rstc = devm_reset_control_array_get_exclusive(dev);
+	ospi->rstc = devm_reset_control_array_get_exclusive_released(dev);
 	if (IS_ERR(ospi->rstc))
 		return dev_err_probe(dev, PTR_ERR(ospi->rstc),
 				     "Can't get reset\n");
@@ -936,11 +936,13 @@ static int stm32_ospi_probe(struct platform_device *pdev)
 	if (ret < 0)
 		goto err_pm_enable;
 
-	if (ospi->rstc) {
-		reset_control_assert(ospi->rstc);
-		udelay(2);
-		reset_control_deassert(ospi->rstc);
-	}
+	ret = reset_control_acquire(ospi->rstc);
+	if (ret)
+		return dev_err_probe(dev, ret, "Can not acquire reset %d\n", ret);
+
+	reset_control_assert(ospi->rstc);
+	udelay(2);
+	reset_control_deassert(ospi->rstc);
 
 	ret = spi_register_controller(ctrl);
 	if (ret) {
@@ -987,6 +989,8 @@ static void stm32_ospi_remove(struct platform_device *pdev)
 	if (ospi->dma_chrx)
 		dma_release_channel(ospi->dma_chrx);
 
+	reset_control_release(ospi->rstc);
+
 	pm_runtime_put_sync_suspend(ospi->dev);
 	pm_runtime_force_suspend(ospi->dev);
 }
@@ -997,6 +1001,8 @@ static int __maybe_unused stm32_ospi_suspend(struct device *dev)
 
 	pinctrl_pm_select_sleep_state(dev);
 
+	reset_control_release(ospi->rstc);
+
 	return pm_runtime_force_suspend(ospi->dev);
 }
 
@@ -1016,6 +1022,12 @@ static int __maybe_unused stm32_ospi_resume(struct device *dev)
 	if (ret < 0)
 		return ret;
 
+	ret = reset_control_acquire(ospi->rstc);
+	if (ret) {
+		dev_err(dev, "Can not acquire reset\n");
+		return ret;
+	}
+
 	writel_relaxed(ospi->cr_reg, regs_base + OSPI_CR);
 	writel_relaxed(ospi->dcr_reg, regs_base + OSPI_DCR1);
 	pm_runtime_mark_last_busy(ospi->dev);