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authorTakashi Iwai <tiwai@suse.de>2017-05-02 08:25:25 +0200
committerTakashi Iwai <tiwai@suse.de>2017-05-02 08:25:25 +0200
commita5c3b32a1146e44f6b38fdfdfffc27842953420c (patch)
treeeca93f51c8deabe77ed079a3e9190717b6380009 /drivers/gpio/gpio-mcp23s08.c
parentd7dc450d5a7162de96edbed6b1792240c2f3a55f (diff)
parent20d5c84bef067b7e804a163e2abca16c47125bad (diff)
Merge tag 'asoc-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Updates for v4.12 A quiet release for the core, but lots of new drivers this time around: - A new, generalized, API for hooking up jacks which makes it easier to write generic machine drivers for simple cases. - Continuing fixes for issues with the x86 CPU drivers. - New drivers for Cirrus CS35L35, DIO DIO2125, Everest ES7132, HiSilicon hi6210, Maxim MAX98927, MT2701 systems with WM8960, Nuvoton NAU8824, Odroid systems, ST STM32 SAI controllers and x86 systems with DA7213
Diffstat (limited to 'drivers/gpio/gpio-mcp23s08.c')
-rw-r--r--drivers/gpio/gpio-mcp23s08.c65
1 files changed, 60 insertions, 5 deletions
diff --git a/drivers/gpio/gpio-mcp23s08.c b/drivers/gpio/gpio-mcp23s08.c
index bdb692345428..2a57d024481d 100644
--- a/drivers/gpio/gpio-mcp23s08.c
+++ b/drivers/gpio/gpio-mcp23s08.c
@@ -270,8 +270,10 @@ mcp23s08_direction_output(struct gpio_chip *chip, unsigned offset, int value)
static irqreturn_t mcp23s08_irq(int irq, void *data)
{
struct mcp23s08 *mcp = data;
- int intcap, intf, i;
+ int intcap, intf, i, gpio, gpio_orig, intcap_mask;
unsigned int child_irq;
+ bool intf_set, intcap_changed, gpio_bit_changed,
+ defval_changed, gpio_set;
mutex_lock(&mcp->lock);
if (mcp_read(mcp, MCP_INTF, &intf) < 0) {
@@ -287,14 +289,67 @@ static irqreturn_t mcp23s08_irq(int irq, void *data)
}
mcp->cache[MCP_INTCAP] = intcap;
+
+ /* This clears the interrupt(configurable on S18) */
+ if (mcp_read(mcp, MCP_GPIO, &gpio) < 0) {
+ mutex_unlock(&mcp->lock);
+ return IRQ_HANDLED;
+ }
+ gpio_orig = mcp->cache[MCP_GPIO];
+ mcp->cache[MCP_GPIO] = gpio;
mutex_unlock(&mcp->lock);
+ if (mcp->cache[MCP_INTF] == 0) {
+ /* There is no interrupt pending */
+ return IRQ_HANDLED;
+ }
+
+ dev_dbg(mcp->chip.parent,
+ "intcap 0x%04X intf 0x%04X gpio_orig 0x%04X gpio 0x%04X\n",
+ intcap, intf, gpio_orig, gpio);
for (i = 0; i < mcp->chip.ngpio; i++) {
- if ((BIT(i) & mcp->cache[MCP_INTF]) &&
- ((BIT(i) & intcap & mcp->irq_rise) ||
- (mcp->irq_fall & ~intcap & BIT(i)) ||
- (BIT(i) & mcp->cache[MCP_INTCON]))) {
+ /* We must check all of the inputs on the chip,
+ * otherwise we may not notice a change on >=2 pins.
+ *
+ * On at least the mcp23s17, INTCAP is only updated
+ * one byte at a time(INTCAPA and INTCAPB are
+ * not written to at the same time - only on a per-bank
+ * basis).
+ *
+ * INTF only contains the single bit that caused the
+ * interrupt per-bank. On the mcp23s17, there is
+ * INTFA and INTFB. If two pins are changed on the A
+ * side at the same time, INTF will only have one bit
+ * set. If one pin on the A side and one pin on the B
+ * side are changed at the same time, INTF will have
+ * two bits set. Thus, INTF can't be the only check
+ * to see if the input has changed.
+ */
+
+ intf_set = BIT(i) & mcp->cache[MCP_INTF];
+ if (i < 8 && intf_set)
+ intcap_mask = 0x00FF;
+ else if (i >= 8 && intf_set)
+ intcap_mask = 0xFF00;
+ else
+ intcap_mask = 0x00;
+
+ intcap_changed = (intcap_mask &
+ (BIT(i) & mcp->cache[MCP_INTCAP])) !=
+ (intcap_mask & (BIT(i) & gpio_orig));
+ gpio_set = BIT(i) & mcp->cache[MCP_GPIO];
+ gpio_bit_changed = (BIT(i) & gpio_orig) !=
+ (BIT(i) & mcp->cache[MCP_GPIO]);
+ defval_changed = (BIT(i) & mcp->cache[MCP_INTCON]) &&
+ ((BIT(i) & mcp->cache[MCP_GPIO]) !=
+ (BIT(i) & mcp->cache[MCP_DEFVAL]));
+
+ if (((gpio_bit_changed || intcap_changed) &&
+ (BIT(i) & mcp->irq_rise) && gpio_set) ||
+ ((gpio_bit_changed || intcap_changed) &&
+ (BIT(i) & mcp->irq_fall) && !gpio_set) ||
+ defval_changed) {
child_irq = irq_find_mapping(mcp->chip.irqdomain, i);
handle_nested_irq(child_irq);
}