mfd: Support of hierachical interrupt for ab8500
Hierarchical interrupt is supported since ab8500 V2.
However, it is not implemented in the ab8500-core driver.
With the current implementation, when an ab9540 interrupt
occurs, 17 Latch registers are read through i2c. With
hierarchical interrupt implementation, there are only 4 i2c
accesses.
Signed-off-by: Maxime Coquelin <maxime.coquelin@stericsson.com>
Reviewed-by: Michel Jaouen <michel.jaouen@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/ab8500-core.c b/drivers/mfd/ab8500-core.c
index 08850f0..6a59919 100644
--- a/drivers/mfd/ab8500-core.c
+++ b/drivers/mfd/ab8500-core.c
@@ -91,6 +91,15 @@
#define AB8500_IT_MASK23_REG 0x56
#define AB8500_IT_MASK24_REG 0x57
+/*
+ * latch hierarchy registers
+ */
+#define AB8500_IT_LATCHHIER1_REG 0x60
+#define AB8500_IT_LATCHHIER2_REG 0x61
+#define AB8500_IT_LATCHHIER3_REG 0x62
+
+#define AB8500_IT_LATCHHIER_NUM 3
+
#define AB8500_REV_REG 0x80
#define AB8500_IC_NAME_REG 0x82
#define AB8500_SWITCH_OFF_STATUS 0x00
@@ -340,6 +349,90 @@
.irq_unmask = ab8500_irq_unmask,
};
+static int ab8500_handle_hierarchical_line(struct ab8500 *ab8500,
+ int latch_offset, u8 latch_val)
+{
+ int int_bit = __ffs(latch_val);
+ int line, i;
+
+ do {
+ int_bit = __ffs(latch_val);
+
+ for (i = 0; i < ab8500->mask_size; i++)
+ if (ab8500->irq_reg_offset[i] == latch_offset)
+ break;
+
+ if (i >= ab8500->mask_size) {
+ dev_err(ab8500->dev, "Register offset 0x%2x not declared\n",
+ latch_offset);
+ return -ENXIO;
+ }
+
+ line = (i << 3) + int_bit;
+ latch_val &= ~(1 << int_bit);
+
+ handle_nested_irq(ab8500->irq_base + line);
+ } while (latch_val);
+
+ return 0;
+}
+
+static int ab8500_handle_hierarchical_latch(struct ab8500 *ab8500,
+ int hier_offset, u8 hier_val)
+{
+ int latch_bit, status;
+ u8 latch_offset, latch_val;
+
+ do {
+ latch_bit = __ffs(hier_val);
+ latch_offset = (hier_offset << 3) + latch_bit;
+
+ /* Fix inconsistent ITFromLatch25 bit mapping... */
+ if (unlikely(latch_offset == 17))
+ latch_offset = 24;
+
+ status = get_register_interruptible(ab8500,
+ AB8500_INTERRUPT,
+ AB8500_IT_LATCH1_REG + latch_offset,
+ &latch_val);
+ if (status < 0 || latch_val == 0)
+ goto discard;
+
+ status = ab8500_handle_hierarchical_line(ab8500,
+ latch_offset, latch_val);
+ if (status < 0)
+ return status;
+discard:
+ hier_val &= ~(1 << latch_bit);
+ } while (hier_val);
+
+ return 0;
+}
+
+static irqreturn_t ab8500_hierarchical_irq(int irq, void *dev)
+{
+ struct ab8500 *ab8500 = dev;
+ u8 i;
+
+ dev_vdbg(ab8500->dev, "interrupt\n");
+
+ /* Hierarchical interrupt version */
+ for (i = 0; i < AB8500_IT_LATCHHIER_NUM; i++) {
+ int status;
+ u8 hier_val;
+
+ status = get_register_interruptible(ab8500, AB8500_INTERRUPT,
+ AB8500_IT_LATCHHIER1_REG + i, &hier_val);
+ if (status < 0 || hier_val == 0)
+ continue;
+
+ status = ab8500_handle_hierarchical_latch(ab8500, i, hier_val);
+ if (status < 0)
+ break;
+ }
+ return IRQ_HANDLED;
+}
+
static irqreturn_t ab8500_irq(int irq, void *dev)
{
struct ab8500 *ab8500 = dev;
@@ -1179,9 +1272,18 @@
if (ret)
goto out_freeoldmask;
- ret = request_threaded_irq(ab8500->irq, NULL, ab8500_irq,
- IRQF_ONESHOT | IRQF_NO_SUSPEND,
- "ab8500", ab8500);
+ /* Activate this feature only in ab9540 */
+ /* till tests are done on ab8500 1p2 or later*/
+ if (is_ab9540(ab8500))
+ ret = request_threaded_irq(ab8500->irq, NULL,
+ ab8500_hierarchical_irq,
+ IRQF_ONESHOT | IRQF_NO_SUSPEND,
+ "ab8500", ab8500);
+ else
+ ret = request_threaded_irq(ab8500->irq, NULL,
+ ab8500_irq,
+ IRQF_ONESHOT | IRQF_NO_SUSPEND,
+ "ab8500", ab8500);
if (ret)
goto out_removeirq;
}