ASoC: davinci-mcasp: Validate tdm_slots parameter at probe time

Instead of validating the tdm_slots parameter every time at hw_params we
can do it once during probe. If the parameter is not valid (<2 or >32)
print an error and fix it up.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 18 insertions, 10 deletions

diff --git a/sound/soc/davinci/davinci-mcasp.c b/sound/soc/davinci/davinci-mcasp.c
index 6b1bfd9de57d..10c264738a0b 100644
--- a/sound/soc/davinci/davinci-mcasp.c
+++ b/sound/soc/davinci/davinci-mcasp.c
@@ -632,13 +632,7 @@ static int mcasp_i2s_hw_param(struct davinci_mcasp *mcasp, int stream)
         u32 mask = 0;
         u32 busel = 0;
 
-        if ((mcasp->tdm_slots < 2) || (mcasp->tdm_slots > 32)) {
-                dev_err(mcasp->dev, "tdm slot %d not supported\n",
-                        mcasp->tdm_slots);
-                return -EINVAL;
-        }
-
-        active_slots = (mcasp->tdm_slots > 31) ? 32 : mcasp->tdm_slots;
+        active_slots = mcasp->tdm_slots;
         for (i = 0; i < active_slots; i++)
                 mask |= (1 << i);
 
@@ -650,12 +644,12 @@ static int mcasp_i2s_hw_param(struct davinci_mcasp *mcasp, int stream)
         mcasp_set_reg(mcasp, DAVINCI_MCASP_TXTDM_REG, mask);
         mcasp_set_bits(mcasp, DAVINCI_MCASP_TXFMT_REG, busel | TXORD);
         mcasp_mod_bits(mcasp, DAVINCI_MCASP_TXFMCTL_REG,
-                       FSXMOD(mcasp->tdm_slots), FSXMOD(0x1FF));
+                       FSXMOD(active_slots), FSXMOD(0x1FF));
 
         mcasp_set_reg(mcasp, DAVINCI_MCASP_RXTDM_REG, mask);
         mcasp_set_bits(mcasp, DAVINCI_MCASP_RXFMT_REG, busel | RXORD);
         mcasp_mod_bits(mcasp, DAVINCI_MCASP_RXFMCTL_REG,
-                       FSRMOD(mcasp->tdm_slots), FSRMOD(0x1FF));
+                       FSRMOD(active_slots), FSRMOD(0x1FF));
 
         return 0;
 }
@@ -1237,7 +1231,21 @@ static int davinci_mcasp_probe(struct platform_device *pdev)
         }
 
         mcasp->op_mode = pdata->op_mode;
-        mcasp->tdm_slots = pdata->tdm_slots;
+        /* sanity check for tdm slots parameter */
+        if (mcasp->op_mode == DAVINCI_MCASP_IIS_MODE) {
+                if (pdata->tdm_slots < 2) {
+                        dev_err(&pdev->dev, "invalid tdm slots: %d\n",
+                                pdata->tdm_slots);
+                        mcasp->tdm_slots = 2;
+                } else if (pdata->tdm_slots > 32) {
+                        dev_err(&pdev->dev, "invalid tdm slots: %d\n",
+                                pdata->tdm_slots);
+                        mcasp->tdm_slots = 32;
+                } else {
+                        mcasp->tdm_slots = pdata->tdm_slots;
+                }
+        }
+
         mcasp->num_serializer = pdata->num_serializer;
 #ifdef CONFIG_PM_SLEEP
         mcasp->context.xrsr_regs = devm_kzalloc(&pdev->dev,