[PATCH v3 5/7] i2c: aspeed: Add aspeed_set_slave_busy()
From: Graeme Gregory <hidden>
Date: 2021-06-07 14:57:46
Also in:
linux-arm-kernel, linux-devicetree, linux-i2c, lkml, openbmc
On Wed, May 19, 2021 at 02:49:32PM +0700, Quan Nguyen wrote:
quoted hunk ↗ jump to hunk
Slave i2c device on AST2500 received a lot of slave irq while it is busy processing the response. To handle this case, adds and exports aspeed_set_slave_busy() for controller to temporary stop slave irq while slave is handling the response, and re-enable them again when the response is ready. Signed-off-by: Quan Nguyen <quan@os.amperecomputing.com> --- v3: + First introduce in v3 [Quan] drivers/i2c/busses/i2c-aspeed.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+)diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c index b2e9c8f0ddf7..9926d04831a2 100644 --- a/drivers/i2c/busses/i2c-aspeed.c +++ b/drivers/i2c/busses/i2c-aspeed.c@@ -944,6 +944,26 @@ static int aspeed_i2c_init(struct aspeed_i2c_bus *bus, return 0; } +#if IS_ENABLED(CONFIG_I2C_SLAVE) +void aspeed_set_slave_busy(struct i2c_adapter *adap, bool busy) +{ + struct aspeed_i2c_bus *bus = i2c_get_adapdata(adap); + unsigned long current_mask, flags; + + spin_lock_irqsave(&bus->lock, flags);
This as far as I can see is still a recursive spinlock, and the spinlock debugger seems to agree with me. Graeme
+
+ current_mask = readl(bus->base + ASPEED_I2C_INTR_CTRL_REG);
+ if (busy)
+ current_mask &= ~(ASPEED_I2CD_INTR_RX_DONE | ASPEED_I2CD_INTR_SLAVE_MATCH);
+ else
+ current_mask |= ASPEED_I2CD_INTR_RX_DONE | ASPEED_I2CD_INTR_SLAVE_MATCH;
+ writel(current_mask, bus->base + ASPEED_I2C_INTR_CTRL_REG);
+
+ spin_unlock_irqrestore(&bus->lock, flags);
+}
+EXPORT_SYMBOL_GPL(aspeed_set_slave_busy);
+#endif
+
static int aspeed_i2c_reset(struct aspeed_i2c_bus *bus)
{
struct platform_device *pdev = to_platform_device(bus->dev);
--
2.28.0