[PATCH v3 16/17] ASoC: fsl_ssi: Move DT related code to a separate probe()

From: Nicolin Chen
Date: Sun Jan 14 2018 - 23:23:16 EST

This patch cleans up probe() function by moving all Device Tree
related code into a separate function. It allows the probe() to
be Device Tree independent. This will be very useful for future
integration of imx-ssi driver which has similar functionalities
while exists only because it supports non-DT cases.

This patch also moves symmetric_channels of AC97 from the probe
to the structure snd_soc_dai_driver for simplification.

Additionally, since PowerPC and AC97 use the same pdev pointer
to register a platform device, this patch also unifies related
code.

Signed-off-by: Nicolin Chen <nicoleotsuka@xxxxxxxxx>
Tested-by: Caleb Crome <caleb@xxxxxxxxx>
---
sound/soc/fsl/fsl_ssi.c | 202 +++++++++++++++++++++++++-----------------------
1 file changed, 107 insertions(+), 95 deletions(-)

diff --git a/sound/soc/fsl/fsl_ssi.c b/sound/soc/fsl/fsl_ssi.c
index 20889d8..d2072de 100644
--- a/sound/soc/fsl/fsl_ssi.c
+++ b/sound/soc/fsl/fsl_ssi.c
@@ -239,8 +239,12 @@ struct fsl_ssi_soc_data {
*
* @fiq_params: FIQ stream filtering parameters
*
- * @pdev: Pointer to pdev when using fsl-ssi as sound card (ppc only)
- * TODO: Should be replaced with simple-sound-card
+ * @card_pdev: Platform_device pointer when using fsl-ssi as sound card
+ * (PowerPC or AC97 only)
+ * @card_name: Platform_device name when using fsl-ssi as sound card
+ * (PowerPC or AC97 only)
+ * @card_idx: The index of SSI when registering a sound card
+ * (PowerPC or AC97 only)
*
* @dbg_stats: Debugging statistics
*
@@ -285,7 +289,9 @@ struct fsl_ssi {

struct imx_pcm_fiq_params fiq_params;

- struct platform_device *pdev;
+ struct platform_device *card_pdev;
+ char card_name[32];
+ u32 card_idx;

struct fsl_ssi_dbg dbg_stats;

@@ -1131,6 +1137,7 @@ static const struct snd_soc_component_driver fsl_ssi_component = {

static struct snd_soc_dai_driver fsl_ssi_ac97_dai = {
.bus_control = true,
+ .symmetric_channels = 1,
.probe = fsl_ssi_dai_probe,
.playback = {
.stream_name = "AC97 Playback",
@@ -1282,9 +1289,7 @@ static void make_lowercase(char *s)
static int fsl_ssi_imx_probe(struct platform_device *pdev,
struct fsl_ssi *ssi, void __iomem *iomem)
{
- struct device_node *np = pdev->dev.of_node;
struct device *dev = &pdev->dev;
- u32 dmas[4];
int ret;

/* Backward compatible for a DT without ipg clock name assigned */
@@ -1318,14 +1323,8 @@ static int fsl_ssi_imx_probe(struct platform_device *pdev,
ssi->dma_params_tx.addr = ssi->ssi_phys + REG_SSI_STX0;
ssi->dma_params_rx.addr = ssi->ssi_phys + REG_SSI_SRX0;

- /* Set to dual FIFO mode according to the SDMA sciprt */
- ret = of_property_read_u32_array(np, "dmas", dmas, 4);
- if (ssi->use_dma && !ret && dmas[2] == IMX_DMATYPE_SSI_DUAL) {
- ssi->use_dual_fifo = true;
- /*
- * Use even numbers to avoid channel swap due to SDMA
- * script design
- */
+ /* Use even numbers to avoid channel swap due to SDMA script design */
+ if (ssi->use_dual_fifo) {
ssi->dma_params_tx.maxburst &= ~0x1;
ssi->dma_params_rx.maxburst &= ~0x1;
}
@@ -1366,41 +1365,102 @@ static void fsl_ssi_imx_clean(struct platform_device *pdev, struct fsl_ssi *ssi)
clk_disable_unprepare(ssi->clk);
}

-static int fsl_ssi_probe(struct platform_device *pdev)
+static int fsl_ssi_probe_from_dt(struct fsl_ssi *ssi)
{
- struct fsl_ssi *ssi;
- int ret = 0;
- struct device_node *np = pdev->dev.of_node;
- struct device *dev = &pdev->dev;
+ struct device *dev = ssi->dev;
+ struct device_node *np = dev->of_node;
const struct of_device_id *of_id;
const char *p, *sprop;
const uint32_t *iprop;
- struct resource *res;
- void __iomem *iomem;
- char name[64];
- struct regmap_config regconfig = fsl_ssi_regconfig;
+ u32 dmas[4];
+ int ret;

of_id = of_match_device(fsl_ssi_ids, dev);
if (!of_id || !of_id->data)
return -EINVAL;

- ssi = devm_kzalloc(dev, sizeof(*ssi), GFP_KERNEL);
- if (!ssi)
- return -ENOMEM;
-
ssi->soc = of_id->data;
- ssi->dev = dev;
+
+ ret = of_property_match_string(np, "clock-names", "ipg");
+ /* Get error code if not found */
+ ssi->has_ipg_clk_name = ret >= 0;

/* Check if being used in AC97 mode */
sprop = of_get_property(np, "fsl,mode", NULL);
- if (sprop) {
- if (!strcmp(sprop, "ac97-slave"))
- ssi->dai_fmt = FSLSSI_AC97_DAIFMT;
+ if (sprop && !strcmp(sprop, "ac97-slave")) {
+ ssi->dai_fmt = FSLSSI_AC97_DAIFMT;
+
+ ret = of_property_read_u32(np, "cell-index", &ssi->card_idx);
+ if (ret) {
+ dev_err(dev, "failed to get SSI index property\n");
+ return -EINVAL;
+ }
+ strcpy(ssi->card_name, "ac97-codec");
}

/* Select DMA or FIQ */
ssi->use_dma = !of_property_read_bool(np, "fsl,fiq-stream-filter");

+ /* In synchronous mode, STCK and STFS ports are used by RX as well */
+ if (!of_find_property(np, "fsl,ssi-asynchronous", NULL))
+ ssi->synchronous = true;
+
+ /* Fetch FIFO depth; Set to 8 for older DT without this property */
+ iprop = of_get_property(np, "fsl,fifo-depth", NULL);
+ if (iprop)
+ ssi->fifo_depth = be32_to_cpup(iprop);
+ else
+ ssi->fifo_depth = 8;
+
+ /* Use dual FIFO mode depending on the support from SDMA script */
+ ret = of_property_read_u32_array(np, "dmas", dmas, 4);
+ if (ssi->use_dma && !ret && dmas[2] == IMX_DMATYPE_SSI_DUAL)
+ ssi->use_dual_fifo = true;
+
+ /*
+ * Backward compatible for older bindings by manually triggering the
+ * machine driver's probe(). Use /compatible property, including the
+ * address of CPU DAI driver structure, as the name of machine driver
+ *
+ * If card_name is set by AC97 earlier, bypass here since it uses a
+ * different name to register the device.
+ */
+ if (!ssi->card_name[0] && of_get_property(np, "codec-handle", NULL)) {
+ sprop = of_get_property(of_find_node_by_path("/"),
+ "compatible", NULL);
+ /* Strip "fsl," in the compatible name if applicable */
+ p = strrchr(sprop, ',');
+ if (p)
+ sprop = p + 1;
+ snprintf(ssi->card_name, sizeof(ssi->card_name),
+ "snd-soc-%s", sprop);
+ make_lowercase(ssi->card_name);
+ ssi->card_idx = 0;
+ }
+
+ return 0;
+}
+
+static int fsl_ssi_probe(struct platform_device *pdev)
+{
+ struct regmap_config regconfig = fsl_ssi_regconfig;
+ struct device *dev = &pdev->dev;
+ struct fsl_ssi *ssi;
+ struct resource *res;
+ void __iomem *iomem;
+ int ret = 0;
+
+ ssi = devm_kzalloc(dev, sizeof(*ssi), GFP_KERNEL);
+ if (!ssi)
+ return -ENOMEM;
+
+ ssi->dev = dev;
+
+ /* Probe from DT */
+ ret = fsl_ssi_probe_from_dt(ssi);
+ if (ret)
+ return ret;
+
if (fsl_ssi_is_ac97(ssi)) {
memcpy(&ssi->cpu_dai_drv, &fsl_ssi_ac97_dai,
sizeof(fsl_ssi_ac97_dai));
@@ -1424,15 +1484,11 @@ static int fsl_ssi_probe(struct platform_device *pdev)
REG_SSI_SRMSK / sizeof(uint32_t) + 1;
}

- ret = of_property_match_string(np, "clock-names", "ipg");
- if (ret < 0) {
- ssi->has_ipg_clk_name = false;
- ssi->regs = devm_regmap_init_mmio(dev, iomem, &regconfig);
- } else {
- ssi->has_ipg_clk_name = true;
+ if (ssi->has_ipg_clk_name)
ssi->regs = devm_regmap_init_mmio_clk(dev, "ipg", iomem,
&regconfig);
- }
+ else
+ ssi->regs = devm_regmap_init_mmio(dev, iomem, &regconfig);
if (IS_ERR(ssi->regs)) {
dev_err(dev, "failed to init register map\n");
return PTR_ERR(ssi->regs);
@@ -1444,24 +1500,13 @@ static int fsl_ssi_probe(struct platform_device *pdev)
return ssi->irq;
}

- /* Set software limitations for synchronous mode */
- if (!of_find_property(np, "fsl,ssi-asynchronous", NULL)) {
- if (!fsl_ssi_is_ac97(ssi)) {
- ssi->cpu_dai_drv.symmetric_rates = 1;
- ssi->cpu_dai_drv.symmetric_samplebits = 1;
- ssi->synchronous = true;
- }
-
+ /* Set software limitations for synchronous mode except AC97 */
+ if (ssi->synchronous && !fsl_ssi_is_ac97(ssi)) {
+ ssi->cpu_dai_drv.symmetric_rates = 1;
ssi->cpu_dai_drv.symmetric_channels = 1;
+ ssi->cpu_dai_drv.symmetric_samplebits = 1;
}

- /* Fetch FIFO depth; Set to 8 for older DT without this property */
- iprop = of_get_property(np, "fsl,fifo-depth", NULL);
- if (iprop)
- ssi->fifo_depth = be32_to_cpup(iprop);
- else
- ssi->fifo_depth = 8;
-
/*
* Configure TX and RX DMA watermarks -- when to send a DMA request
*
@@ -1526,50 +1571,17 @@ static int fsl_ssi_probe(struct platform_device *pdev)
if (ret)
goto error_asoc_register;

- /* Bypass it if using newer DT bindings of ASoC machine drivers */
- if (!of_get_property(np, "codec-handle", NULL))
- goto done;
-
- /*
- * Backward compatible for older bindings by manually triggering the
- * machine driver's probe(). Use /compatible property, including the
- * address of CPU DAI driver structure, as the name of machine driver.
- */
- sprop = of_get_property(of_find_node_by_path("/"), "compatible", NULL);
- /* Sometimes the compatible name has a "fsl," prefix, so we strip it. */
- p = strrchr(sprop, ',');
- if (p)
- sprop = p + 1;
- snprintf(name, sizeof(name), "snd-soc-%s", sprop);
- make_lowercase(name);
-
- ssi->pdev = platform_device_register_data(dev, name, 0, NULL, 0);
- if (IS_ERR(ssi->pdev)) {
- ret = PTR_ERR(ssi->pdev);
- dev_err(dev, "failed to register platform: %d\n", ret);
- goto error_sound_card;
- }
-
-done:
/* Initially configures SSI registers */
fsl_ssi_hw_init(ssi);

- if (fsl_ssi_is_ac97(ssi)) {
- u32 ssi_idx;
-
- ret = of_property_read_u32(np, "cell-index", &ssi_idx);
- if (ret) {
- dev_err(dev, "failed to get SSI index property\n");
- goto error_sound_card;
- }
-
- ssi->pdev = platform_device_register_data(NULL, "ac97-codec",
- ssi_idx, NULL, 0);
- if (IS_ERR(ssi->pdev)) {
- ret = PTR_ERR(ssi->pdev);
- dev_err(dev,
- "failed to register AC97 codec platform: %d\n",
- ret);
+ /* Register a platform device for older bindings or AC97 */
+ if (ssi->card_name[0]) {
+ ssi->card_pdev = platform_device_register_data(dev,
+ ssi->card_name, ssi->card_idx, NULL, 0);
+ if (IS_ERR(ssi->card_pdev)) {
+ ret = PTR_ERR(ssi->card_pdev);
+ dev_err(dev, "failed to register %s: %d\n",
+ ssi->card_name, ret);
goto error_sound_card;
}
}
@@ -1599,8 +1611,8 @@ static int fsl_ssi_remove(struct platform_device *pdev)

fsl_ssi_debugfs_remove(&ssi->dbg_stats);

- if (ssi->pdev)
- platform_device_unregister(ssi->pdev);
+ if (ssi->card_pdev)
+ platform_device_unregister(ssi->card_pdev);

if (ssi->soc->imx)
fsl_ssi_imx_clean(pdev, ssi);
--
2.7.4