[PATCH v2 1/6] ASoC: fsl_utils: Add function to handle PLL clock source

From: Shengjiu Wang
Date: Fri Jul 01 2022 - 05:47:46 EST


i.MX8MQ/MN/MM/MP platforms typically have 2 AUDIO PLLs being
configured to handle 8kHz and 11kHz series audio rates.
Add common function in fsl_utils to handle these two PLL
clock source, which are needed by CPU DAI drivers

Signed-off-by: Shengjiu Wang <shengjiu.wang@xxxxxxx>
---
sound/soc/fsl/fsl_utils.c | 69 +++++++++++++++++++++++++++++++++++++++
sound/soc/fsl/fsl_utils.h | 7 ++++
2 files changed, 76 insertions(+)

diff --git a/sound/soc/fsl/fsl_utils.c b/sound/soc/fsl/fsl_utils.c
index 9bab202569af..b75843e31f00 100644
--- a/sound/soc/fsl/fsl_utils.c
+++ b/sound/soc/fsl/fsl_utils.c
@@ -6,6 +6,8 @@
//
// Copyright 2010 Freescale Semiconductor, Inc.

+#include <linux/clk.h>
+#include <linux/clk-provider.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <sound/soc.h>
@@ -83,6 +85,73 @@ int fsl_asoc_get_dma_channel(struct device_node *ssi_np,
}
EXPORT_SYMBOL(fsl_asoc_get_dma_channel);

+/**
+ * fsl_asoc_get_pll_clocks - get two PLL clock source
+ *
+ * @dev: device pointer
+ * @pll8k_clk: PLL clock pointer for 8kHz
+ * @pll11k_clk: PLL clock pointer for 11kHz
+ *
+ * This function get two PLL clock source
+ */
+void fsl_asoc_get_pll_clocks(struct device *dev, struct clk **pll8k_clk,
+ struct clk **pll11k_clk)
+{
+ *pll8k_clk = devm_clk_get(dev, "pll8k");
+ if (IS_ERR(*pll8k_clk))
+ *pll8k_clk = NULL;
+
+ *pll11k_clk = devm_clk_get(dev, "pll11k");
+ if (IS_ERR(*pll11k_clk))
+ *pll11k_clk = NULL;
+}
+EXPORT_SYMBOL(fsl_asoc_get_pll_clocks);
+
+/**
+ * fsl_asoc_reparent_pll_clocks - set clock parent if necessary
+ *
+ * @dev: device pointer
+ * @clk: root clock pointer
+ * @pll8k_clk: PLL clock pointer for 8kHz
+ * @pll11k_clk: PLL clock pointer for 11kHz
+ * @ratio: target requency for root clock
+ *
+ * This function set root clock parent according to the target ratio
+ */
+void fsl_asoc_reparent_pll_clocks(struct device *dev, struct clk *clk,
+ struct clk *pll8k_clk,
+ struct clk *pll11k_clk, u64 ratio)
+{
+ struct clk *p, *pll = 0, *npll = 0;
+ bool reparent = false;
+ int ret = 0;
+
+ if (!clk || !pll8k_clk || !pll11k_clk)
+ return;
+
+ p = clk;
+ while (p && pll8k_clk && pll11k_clk) {
+ struct clk *pp = clk_get_parent(p);
+
+ if (clk_is_match(pp, pll8k_clk) ||
+ clk_is_match(pp, pll11k_clk)) {
+ pll = pp;
+ break;
+ }
+ p = pp;
+ }
+
+ npll = (do_div(ratio, 8000) ? pll11k_clk : pll8k_clk);
+ reparent = (pll && !clk_is_match(pll, npll));
+
+ if (reparent) {
+ ret = clk_set_parent(p, npll);
+ if (ret < 0)
+ dev_warn(dev, "failed to set parent %s: %d\n", __clk_get_name(npll), ret);
+ }
+}
+EXPORT_SYMBOL(fsl_asoc_reparent_pll_clocks);
+
MODULE_AUTHOR("Timur Tabi <timur@xxxxxxxxxxxxx>");
MODULE_DESCRIPTION("Freescale ASoC utility code");
MODULE_LICENSE("GPL v2");
diff --git a/sound/soc/fsl/fsl_utils.h b/sound/soc/fsl/fsl_utils.h
index c5dc2a14b492..4d5f3d93bc81 100644
--- a/sound/soc/fsl/fsl_utils.h
+++ b/sound/soc/fsl/fsl_utils.h
@@ -19,4 +19,11 @@ int fsl_asoc_get_dma_channel(struct device_node *ssi_np, const char *name,
struct snd_soc_dai_link *dai,
unsigned int *dma_channel_id,
unsigned int *dma_id);
+
+void fsl_asoc_get_pll_clocks(struct device *dev, struct clk **pll8k_clk,
+ struct clk **pll11k_clk);
+
+void fsl_asoc_reparent_pll_clocks(struct device *dev, struct clk *clk,
+ struct clk *pll8k_clk,
+ struct clk *pll11k_clk, u64 ratio);
#endif /* _FSL_UTILS_H */
--
2.17.1