3 files changed, 138 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/mcbsp.c b/arch/arm/mach-omap2/mcbsp.c
index a5c0f0435cd6..f837114d1d69 100644
--- a/arch/arm/mach-omap2/mcbsp.c
+++ b/arch/arm/mach-omap2/mcbsp.c
@@ -129,6 +129,7 @@ static struct omap_mcbsp_platform_data omap34xx_mcbsp_pdata[] = {
                 .rx_irq         = INT_24XX_MCBSP1_IRQ_RX,
                 .tx_irq         = INT_24XX_MCBSP1_IRQ_TX,
                 .ops            = &omap2_mcbsp_ops,
+                .buffer_size    = 0x7F,
         },
         {
                 .phys_base      = OMAP34XX_MCBSP2_BASE,
@@ -137,6 +138,7 @@ static struct omap_mcbsp_platform_data omap34xx_mcbsp_pdata[] = {
                 .rx_irq         = INT_24XX_MCBSP2_IRQ_RX,
                 .tx_irq         = INT_24XX_MCBSP2_IRQ_TX,
                 .ops            = &omap2_mcbsp_ops,
+                .buffer_size    = 0x3FF,
         },
         {
                 .phys_base      = OMAP34XX_MCBSP3_BASE,
@@ -145,6 +147,7 @@ static struct omap_mcbsp_platform_data omap34xx_mcbsp_pdata[] = {
                 .rx_irq         = INT_24XX_MCBSP3_IRQ_RX,
                 .tx_irq         = INT_24XX_MCBSP3_IRQ_TX,
                 .ops            = &omap2_mcbsp_ops,
+                .buffer_size    = 0x7F,
         },
         {
                 .phys_base      = OMAP34XX_MCBSP4_BASE,
@@ -153,6 +156,7 @@ static struct omap_mcbsp_platform_data omap34xx_mcbsp_pdata[] = {
                 .rx_irq         = INT_24XX_MCBSP4_IRQ_RX,
                 .tx_irq         = INT_24XX_MCBSP4_IRQ_TX,
                 .ops            = &omap2_mcbsp_ops,
+                .buffer_size    = 0x7F,
         },
         {
                 .phys_base      = OMAP34XX_MCBSP5_BASE,
@@ -161,6 +165,7 @@ static struct omap_mcbsp_platform_data omap34xx_mcbsp_pdata[] = {
                 .rx_irq         = INT_24XX_MCBSP5_IRQ_RX,
                 .tx_irq         = INT_24XX_MCBSP5_IRQ_TX,
                 .ops            = &omap2_mcbsp_ops,
+                .buffer_size    = 0x7F,
         },
 };
 #define OMAP34XX_MCBSP_PDATA_SZ         ARRAY_SIZE(omap34xx_mcbsp_pdata)
diff --git a/arch/arm/plat-omap/include/mach/mcbsp.h b/arch/arm/plat-omap/include/mach/mcbsp.h
index 2544aa5bccd3..832330d7cb39 100644
--- a/arch/arm/plat-omap/include/mach/mcbsp.h
+++ b/arch/arm/plat-omap/include/mach/mcbsp.h
@@ -348,6 +348,9 @@ struct omap_mcbsp_platform_data {
         u8 dma_rx_sync, dma_tx_sync;
         u16 rx_irq, tx_irq;
         struct omap_mcbsp_ops *ops;
+#ifdef CONFIG_ARCH_OMAP34XX
+        u16 buffer_size;
+#endif
 };
 
 struct omap_mcbsp {
@@ -381,6 +384,10 @@ struct omap_mcbsp {
         struct omap_mcbsp_platform_data *pdata;
         struct clk *iclk;
         struct clk *fclk;
+#ifdef CONFIG_ARCH_OMAP34XX
+        u16 max_tx_thres;
+        u16 max_rx_thres;
+#endif
 };
 extern struct omap_mcbsp **mcbsp_ptr;
 extern int omap_mcbsp_count;
@@ -392,11 +399,15 @@ void omap_mcbsp_config(unsigned int id, const struct omap_mcbsp_reg_cfg * config
 #ifdef CONFIG_ARCH_OMAP34XX
 void omap_mcbsp_set_tx_threshold(unsigned int id, u16 threshold);
 void omap_mcbsp_set_rx_threshold(unsigned int id, u16 threshold);
+u16 omap_mcbsp_get_max_tx_threshold(unsigned int id);
+u16 omap_mcbsp_get_max_rx_threshold(unsigned int id);
 #else
 static inline void omap_mcbsp_set_tx_threshold(unsigned int id, u16 threshold)
 { }
 static inline void omap_mcbsp_set_rx_threshold(unsigned int id, u16 threshold)
 { }
+static inline u16 omap_mcbsp_get_max_tx_threshold(unsigned int id) { return 0; }
+static inline u16 omap_mcbsp_get_max_rx_threshold(unsigned int id) { return 0; }
 #endif
 int omap_mcbsp_request(unsigned int id);
 void omap_mcbsp_free(unsigned int id);
diff --git a/arch/arm/plat-omap/mcbsp.c b/arch/arm/plat-omap/mcbsp.c
index 081f2eace92d..0bbc912e548d 100644
--- a/arch/arm/plat-omap/mcbsp.c
+++ b/arch/arm/plat-omap/mcbsp.c
@@ -246,6 +246,42 @@ void omap_mcbsp_set_rx_threshold(unsigned int id, u16 threshold)
         OMAP_MCBSP_WRITE(io_base, THRSH1, threshold);
 }
 EXPORT_SYMBOL(omap_mcbsp_set_rx_threshold);
+
+/*
+ * omap_mcbsp_get_max_tx_thres just return the current configured
+ * maximum threshold for transmission
+ */
+u16 omap_mcbsp_get_max_tx_threshold(unsigned int id)
+{
+        struct omap_mcbsp *mcbsp;
+
+        if (!omap_mcbsp_check_valid_id(id)) {
+                printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
+                return -ENODEV;
+        }
+        mcbsp = id_to_mcbsp_ptr(id);
+
+        return mcbsp->max_tx_thres;
+}
+EXPORT_SYMBOL(omap_mcbsp_get_max_tx_threshold);
+
+/*
+ * omap_mcbsp_get_max_rx_thres just return the current configured
+ * maximum threshold for reception
+ */
+u16 omap_mcbsp_get_max_rx_threshold(unsigned int id)
+{
+        struct omap_mcbsp *mcbsp;
+
+        if (!omap_mcbsp_check_valid_id(id)) {
+                printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
+                return -ENODEV;
+        }
+        mcbsp = id_to_mcbsp_ptr(id);
+
+        return mcbsp->max_rx_thres;
+}
+EXPORT_SYMBOL(omap_mcbsp_get_max_rx_threshold);
 #endif
 
 /*
@@ -1005,6 +1041,86 @@ void omap_mcbsp_set_spi_mode(unsigned int id,
 }
 EXPORT_SYMBOL(omap_mcbsp_set_spi_mode);
 
+#ifdef CONFIG_ARCH_OMAP34XX
+#define max_thres(m)                    (mcbsp->pdata->buffer_size)
+#define valid_threshold(m, val)         ((val) <= max_thres(m))
+#define THRESHOLD_PROP_BUILDER(prop)                                    \
+static ssize_t prop##_show(struct device *dev,                          \
+                        struct device_attribute *attr, char *buf)       \
+{                                                                       \
+        struct omap_mcbsp *mcbsp = dev_get_drvdata(dev);                \
+                                                                        \
+        return sprintf(buf, "%u\n", mcbsp->prop);                       \
+}                                                                       \
+                                                                        \
+static ssize_t prop##_store(struct device *dev,                         \
+                                struct device_attribute *attr,          \
+                                const char *buf, size_t size)           \
+{                                                                       \
+        struct omap_mcbsp *mcbsp = dev_get_drvdata(dev);                \
+        unsigned long val;                                              \
+        int status;                                                     \
+                                                                        \
+        status = strict_strtoul(buf, 0, &val);                          \
+        if (status)                                                     \
+                return status;                                          \
+                                                                        \
+        if (!valid_threshold(mcbsp, val))                               \
+                return -EDOM;                                           \
+                                                                        \
+        mcbsp->prop = val;                                              \
+        return size;                                                    \
+}                                                                       \
+                                                                        \
+static DEVICE_ATTR(prop, 0644, prop##_show, prop##_store);
+
+THRESHOLD_PROP_BUILDER(max_tx_thres);
+THRESHOLD_PROP_BUILDER(max_rx_thres);
+
+static const struct attribute *threshold_attrs[] = {
+        &dev_attr_max_tx_thres.attr,
+        &dev_attr_max_rx_thres.attr,
+        NULL,
+};
+
+static const struct attribute_group threshold_attr_group = {
+        .attrs = (struct attribute **)threshold_attrs,
+};
+
+static inline int __devinit omap_thres_add(struct device *dev)
+{
+        return sysfs_create_group(&dev->kobj, &threshold_attr_group);
+}
+
+static inline void __devexit omap_thres_remove(struct device *dev)
+{
+        sysfs_remove_group(&dev->kobj, &threshold_attr_group);
+}
+
+static inline void __devinit omap34xx_device_init(struct omap_mcbsp *mcbsp)
+{
+        if (cpu_is_omap34xx()) {
+                mcbsp->max_tx_thres = max_thres(mcbsp);
+                mcbsp->max_rx_thres = max_thres(mcbsp);
+                if (omap_thres_add(mcbsp->dev))
+                        dev_warn(mcbsp->dev,
+                                "Unable to create threshold controls\n");
+        } else {
+                mcbsp->max_tx_thres = -EINVAL;
+                mcbsp->max_rx_thres = -EINVAL;
+        }
+}
+
+static inline void __devexit omap34xx_device_exit(struct omap_mcbsp *mcbsp)
+{
+        if (cpu_is_omap34xx())
+                omap_thres_remove(mcbsp->dev);
+}
+#else
+static inline void __devinit omap34xx_device_init(struct omap_mcbsp *mcbsp) {}
+static inline void __devexit omap34xx_device_exit(struct omap_mcbsp *mcbsp) {}
+#endif /* CONFIG_ARCH_OMAP34XX */
+
 /*
  * McBSP1 and McBSP3 are directly mapped on 1610 and 1510.
  * 730 has only 2 McBSP, and both of them are MPU peripherals.
@@ -1075,6 +1191,10 @@ static int __devinit omap_mcbsp_probe(struct platform_device *pdev)
         mcbsp->dev = &pdev->dev;
         mcbsp_ptr[id] = mcbsp;
         platform_set_drvdata(pdev, mcbsp);
+
+        /* Initialize mcbsp properties for OMAP34XX if needed / applicable */
+        omap34xx_device_init(mcbsp);
+
         return 0;
 
 err_fclk:
@@ -1098,6 +1218,8 @@ static int __devexit omap_mcbsp_remove(struct platform_device *pdev)
                                 mcbsp->pdata->ops->free)
                         mcbsp->pdata->ops->free(mcbsp->id);
 
+                omap34xx_device_exit(mcbsp);
+
                 clk_disable(mcbsp->fclk);
                 clk_disable(mcbsp->iclk);
                 clk_put(mcbsp->fclk);