mfd: Add support for stmpe variant 801

STMPE801 is a GPIO expander. Registers for 801 are much different from other
variants. This patch adds support for STMPE801 in stmpe mfd driver.

Signed-off-by: Bhupesh Sharma <bhupesh.sharma@st.com>
Signed-off-by: Pratyush Anand <pratyush.anand@st.com>
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

5 files changed, 106 insertions, 13 deletions

diff --git a/drivers/mfd/stmpe-i2c.c b/drivers/mfd/stmpe-i2c.c
index b11d33b1c89..373f423b118 100644
--- a/drivers/mfd/stmpe-i2c.c
+++ b/drivers/mfd/stmpe-i2c.c
@@ -72,6 +72,7 @@ static int __devexit stmpe_i2c_remove(struct i2c_client *i2c)
 
 static const struct i2c_device_id stmpe_i2c_id[] = {
         { "stmpe610", STMPE610 },
+        { "stmpe801", STMPE801 },
         { "stmpe811", STMPE811 },
         { "stmpe1601", STMPE1601 },
         { "stmpe2401", STMPE2401 },
diff --git a/drivers/mfd/stmpe-spi.c b/drivers/mfd/stmpe-spi.c
index 46963a5d569..b58c43c7ea9 100644
--- a/drivers/mfd/stmpe-spi.c
+++ b/drivers/mfd/stmpe-spi.c
@@ -110,6 +110,7 @@ static int __devexit stmpe_spi_remove(struct spi_device *spi)
 
 static const struct spi_device_id stmpe_spi_id[] = {
         { "stmpe610", STMPE610 },
+        { "stmpe801", STMPE801 },
         { "stmpe811", STMPE811 },
         { "stmpe1601", STMPE1601 },
         { "stmpe2401", STMPE2401 },
diff --git a/drivers/mfd/stmpe.c b/drivers/mfd/stmpe.c
index 67ff3dc5bb4..fc2c6afb31e 100644
--- a/drivers/mfd/stmpe.c
+++ b/drivers/mfd/stmpe.c
@@ -241,12 +241,14 @@ int stmpe_set_altfunc(struct stmpe *stmpe, u32 pins, enum stmpe_block block)
         u8 regaddr = stmpe->regs[STMPE_IDX_GPAFR_U_MSB];
         int af_bits = variant->af_bits;
         int numregs = DIV_ROUND_UP(stmpe->num_gpios * af_bits, 8);
-        int afperreg = 8 / af_bits;
         int mask = (1 << af_bits) - 1;
         u8 regs[numregs];
-        int af;
-        int ret;
+        int af, afperreg, ret;
+
+        if (!variant->get_altfunc)
+                return 0;
 
+        afperreg = 8 / af_bits;
         mutex_lock(&stmpe->lock);
 
         ret = __stmpe_enable(stmpe, STMPE_BLOCK_GPIO);
@@ -321,6 +323,50 @@ static struct mfd_cell stmpe_keypad_cell = {
 };
 
 /*
+ * STMPE801
+ */
+static const u8 stmpe801_regs[] = {
+        [STMPE_IDX_CHIP_ID]     = STMPE801_REG_CHIP_ID,
+        [STMPE_IDX_ICR_LSB]     = STMPE801_REG_SYS_CTRL,
+        [STMPE_IDX_GPMR_LSB]    = STMPE801_REG_GPIO_MP_STA,
+        [STMPE_IDX_GPSR_LSB]    = STMPE801_REG_GPIO_SET_PIN,
+        [STMPE_IDX_GPCR_LSB]    = STMPE801_REG_GPIO_SET_PIN,
+        [STMPE_IDX_GPDR_LSB]    = STMPE801_REG_GPIO_DIR,
+        [STMPE_IDX_IEGPIOR_LSB] = STMPE801_REG_GPIO_INT_EN,
+        [STMPE_IDX_ISGPIOR_MSB] = STMPE801_REG_GPIO_INT_STA,
+
+};
+
+static struct stmpe_variant_block stmpe801_blocks[] = {
+        {
+                .cell   = &stmpe_gpio_cell,
+                .irq    = 0,
+                .block  = STMPE_BLOCK_GPIO,
+        },
+};
+
+static int stmpe801_enable(struct stmpe *stmpe, unsigned int blocks,
+                           bool enable)
+{
+        if (blocks & STMPE_BLOCK_GPIO)
+                return 0;
+        else
+                return -EINVAL;
+}
+
+static struct stmpe_variant_info stmpe801 = {
+        .name           = "stmpe801",
+        .id_val         = STMPE801_ID,
+        .id_mask        = 0xffff,
+        .num_gpios      = 8,
+        .regs           = stmpe801_regs,
+        .blocks         = stmpe801_blocks,
+        .num_blocks     = ARRAY_SIZE(stmpe801_blocks),
+        .num_irqs       = STMPE801_NR_INTERNAL_IRQS,
+        .enable         = stmpe801_enable,
+};
+
+/*
  * Touchscreen (STMPE811 or STMPE610)
  */
 
@@ -667,6 +713,7 @@ static struct stmpe_variant_info stmpe2403 = {
 
 static struct stmpe_variant_info *stmpe_variant_info[] = {
         [STMPE610]      = &stmpe610,
+        [STMPE801]      = &stmpe801,
         [STMPE811]      = &stmpe811,
         [STMPE1601]     = &stmpe1601,
         [STMPE2401]     = &stmpe2401,
@@ -683,6 +730,11 @@ static irqreturn_t stmpe_irq(int irq, void *data)
         int ret;
         int i;
 
+        if (variant->id_val == STMPE801_ID) {
+                handle_nested_irq(stmpe->irq_base);
+                return IRQ_HANDLED;
+        }
+
         ret = stmpe_block_read(stmpe, israddr, num, isr);
         if (ret < 0)
                 return IRQ_NONE;
@@ -769,14 +821,17 @@ static struct irq_chip stmpe_irq_chip = {
 
 static int __devinit stmpe_irq_init(struct stmpe *stmpe)
 {
+        struct irq_chip *chip = NULL;
         int num_irqs = stmpe->variant->num_irqs;
         int base = stmpe->irq_base;
         int irq;
 
+        if (stmpe->variant->id_val != STMPE801_ID)
+                chip = &stmpe_irq_chip;
+
         for (irq = base; irq < base + num_irqs; irq++) {
                 irq_set_chip_data(irq, stmpe);
-                irq_set_chip_and_handler(irq, &stmpe_irq_chip,
-                                         handle_edge_irq);
+                irq_set_chip_and_handler(irq, chip, handle_edge_irq);
                 irq_set_nested_thread(irq, 1);
 #ifdef CONFIG_ARM
                 set_irq_flags(irq, IRQF_VALID);
@@ -808,7 +863,7 @@ static int __devinit stmpe_chip_init(struct stmpe *stmpe)
         unsigned int irq_trigger = stmpe->pdata->irq_trigger;
         int autosleep_timeout = stmpe->pdata->autosleep_timeout;
         struct stmpe_variant_info *variant = stmpe->variant;
-        u8 icr = STMPE_ICR_LSB_GIM;
+        u8 icr;
         unsigned int id;
         u8 data[2];
         int ret;
@@ -831,16 +886,32 @@ static int __devinit stmpe_chip_init(struct stmpe *stmpe)
         if (ret)
                 return ret;
 
-        if (irq_trigger == IRQF_TRIGGER_FALLING ||
-            irq_trigger == IRQF_TRIGGER_RISING)
-                icr |= STMPE_ICR_LSB_EDGE;
+        if (id == STMPE801_ID)
+                icr = STMPE801_REG_SYS_CTRL_INT_EN;
+        else
+                icr = STMPE_ICR_LSB_GIM;
+
+        /* STMPE801 doesn't support Edge interrupts */
+        if (id != STMPE801_ID) {
+                if (irq_trigger == IRQF_TRIGGER_FALLING ||
+                                irq_trigger == IRQF_TRIGGER_RISING)
+                        icr |= STMPE_ICR_LSB_EDGE;
+        }
 
         if (irq_trigger == IRQF_TRIGGER_RISING ||
-            irq_trigger == IRQF_TRIGGER_HIGH)
-                icr |= STMPE_ICR_LSB_HIGH;
+                        irq_trigger == IRQF_TRIGGER_HIGH) {
+                if (id == STMPE801_ID)
+                        icr |= STMPE801_REG_SYS_CTRL_INT_HI;
+                else
+                        icr |= STMPE_ICR_LSB_HIGH;
+        }
 
-        if (stmpe->pdata->irq_invert_polarity)
-                icr ^= STMPE_ICR_LSB_HIGH;
+        if (stmpe->pdata->irq_invert_polarity) {
+                if (id == STMPE801_ID)
+                        icr ^= STMPE801_REG_SYS_CTRL_INT_HI;
+                else
+                        icr ^= STMPE_ICR_LSB_HIGH;
+        }
 
         if (stmpe->pdata->autosleep) {
                 ret = stmpe_autosleep(stmpe, autosleep_timeout);
diff --git a/drivers/mfd/stmpe.h b/drivers/mfd/stmpe.h
index a73f4c1085f..7b8e13f5b76 100644
--- a/drivers/mfd/stmpe.h
+++ b/drivers/mfd/stmpe.h
@@ -105,6 +105,25 @@ int stmpe_remove(struct stmpe *stmpe);
 #define STMPE_ICR_LSB_GIM       (1 << 0)
 
 /*
+ * STMPE801
+ */
+#define STMPE801_ID                     0x0108
+#define STMPE801_NR_INTERNAL_IRQS       1
+
+#define STMPE801_REG_CHIP_ID            0x00
+#define STMPE801_REG_VERSION_ID         0x02
+#define STMPE801_REG_SYS_CTRL           0x04
+#define STMPE801_REG_GPIO_INT_EN        0x08
+#define STMPE801_REG_GPIO_INT_STA       0x09
+#define STMPE801_REG_GPIO_MP_STA        0x10
+#define STMPE801_REG_GPIO_SET_PIN       0x11
+#define STMPE801_REG_GPIO_DIR           0x12
+
+#define STMPE801_REG_SYS_CTRL_RESET     (1 << 7)
+#define STMPE801_REG_SYS_CTRL_INT_EN    (1 << 2)
+#define STMPE801_REG_SYS_CTRL_INT_HI    (1 << 0)
+
+/*
  * STMPE811
  */
 
diff --git a/include/linux/mfd/stmpe.h b/include/linux/mfd/stmpe.h
index 342005afd34..ca1d7a34760 100644
--- a/include/linux/mfd/stmpe.h
+++ b/include/linux/mfd/stmpe.h
@@ -21,6 +21,7 @@ enum stmpe_block {
 
 enum stmpe_partnum {
         STMPE610,
+        STMPE801,
         STMPE811,
         STMPE1601,
         STMPE2401,