[PATCH v3 5/7] i2c: aspeed: Add aspeed_set_slave_busy()

[Quan Nguyen]

On 24/05/2021 17:06, Ryan Chen wrote:
>> -----Original Message-----
>> From: openbmc
>> <openbmc-bounces+ryan_chen=aspeedtech.com at lists.ozlabs.org> On Behalf
>> Of Quan Nguyen
>> Sent: Wednesday, May 19, 2021 3:50 PM
>> To: Corey Minyard <minyard at acm.org>; Rob Herring <robh+dt at kernel.org>;
>> Joel Stanley <joel at jms.id.au>; Andrew Jeffery <andrew at aj.id.au>; Brendan
>> Higgins <brendanhiggins at google.com>; Benjamin Herrenschmidt
>> <benh at kernel.crashing.org>; Wolfram Sang <wsa at kernel.org>; Philipp Zabel
>> <p.zabel at pengutronix.de>; openipmi-developer at lists.sourceforge.net;
>> devicetree at vger.kernel.org; linux-arm-kernel at lists.infradead.org;
>> linux-aspeed at lists.ozlabs.org; linux-kernel at vger.kernel.org;
>> linux-i2c at vger.kernel.org
>> Cc: Open Source Submission <patches at amperecomputing.com>; Thang Q .
>> Nguyen <thang at os.amperecomputing.com>; Phong Vo
>> <phong at os.amperecomputing.com>; openbmc at lists.ozlabs.org
>> Subject: [PATCH v3 5/7] i2c: aspeed: Add aspeed_set_slave_busy()
>>
>> 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 at 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);
>> +
>> +	current_mask = readl(bus->base + ASPEED_I2C_INTR_CTRL_REG);
> Hello
> 	Where the bus->base to be remap?
> 

Hi Ryan,

In "[PATCH v3 6/7] ipmi: ssif_bmc: Add Aspeed SSIF BMC driver", the 
->priv is retrieved by calling i2c_get_adapdata(client->adapter). And in 
aspeed_set_ssif_bmc_status(), call the exported aspeed_set_slave_busy() 
using ->priv pointer as code below.

+extern void aspeed_set_slave_busy(struct i2c_adapter *adap, bool busy);
+static void aspeed_set_ssif_bmc_status(struct ssif_bmc_ctx *ssif_bmc, 
unsigned int status)
+{
+	if (status & SSIF_BMC_BUSY)
+		aspeed_set_slave_busy((struct i2c_adapter *)ssif_bmc->priv, true);
+	else if (status & SSIF_BMC_READY)
+		aspeed_set_slave_busy((struct i2c_adapter *)ssif_bmc->priv, false);
+}
+
+static int ssif_bmc_probe(struct i2c_client *client, const struct 
i2c_device_id *id)
+{
+	struct ssif_bmc_ctx *ssif_bmc;
+
+	ssif_bmc = ssif_bmc_alloc(client, 0);
+	if (IS_ERR(ssif_bmc))
+		return PTR_ERR(ssif_bmc);
+
+	ssif_bmc->priv = i2c_get_adapdata(client->adapter);
+	ssif_bmc->set_ssif_bmc_status = aspeed_set_ssif_bmc_status;
+
+	return 0;
+}

- Quan