Re: [PATCH v3 5/7] i2c: aspeed: Add aspeed_set_slave_busy()
From: Quan Nguyen
Date: Thu May 27 2021 - 20:53:53 EST
On 25/05/2021 17:30, Ryan Chen wrote:
-----Original Message-----
From: Quan Nguyen <quan@xxxxxxxxxxxxxxxxxxxxxx>
Sent: Monday, May 24, 2021 6:49 PM
To: Ryan Chen <ryan_chen@xxxxxxxxxxxxxx>; Corey Minyard
<minyard@xxxxxxx>; Rob Herring <robh+dt@xxxxxxxxxx>; Joel Stanley
<joel@xxxxxxxxx>; Andrew Jeffery <andrew@xxxxxxxx>; Brendan Higgins
<brendanhiggins@xxxxxxxxxx>; Benjamin Herrenschmidt
<benh@xxxxxxxxxxxxxxxxxxx>; Wolfram Sang <wsa@xxxxxxxxxx>; Philipp Zabel
<p.zabel@xxxxxxxxxxxxxx>; openipmi-developer@xxxxxxxxxxxxxxxxxxxxx;
devicetree@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
linux-aspeed@xxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
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Cc: Open Source Submission <patches@xxxxxxxxxxxxxxxxxxx>; Thang Q .
Nguyen <thang@xxxxxxxxxxxxxxxxxxxxxx>; Phong Vo
<phong@xxxxxxxxxxxxxxxxxxxxxx>; openbmc@xxxxxxxxxxxxxxxx
Subject: Re: [PATCH v3 5/7] i2c: aspeed: Add aspeed_set_slave_busy()
On 24/05/2021 17:36, Ryan Chen wrote:
-----Original Message-----
From: Quan Nguyen <quan@xxxxxxxxxxxxxxxxxxxxxx>
Sent: Monday, May 24, 2021 6:20 PM
To: Ryan Chen <ryan_chen@xxxxxxxxxxxxxx>; Corey Minyard
<minyard@xxxxxxx>; Rob Herring <robh+dt@xxxxxxxxxx>; Joel Stanley
<joel@xxxxxxxxx>; Andrew Jeffery <andrew@xxxxxxxx>; Brendan Higgins
<brendanhiggins@xxxxxxxxxx>; Benjamin Herrenschmidt
<benh@xxxxxxxxxxxxxxxxxxx>; Wolfram Sang <wsa@xxxxxxxxxx>; Philipp
Zabel <p.zabel@xxxxxxxxxxxxxx>;
openipmi-developer@xxxxxxxxxxxxxxxxxxxxx;
devicetree@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
linux-aspeed@xxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
linux-i2c@xxxxxxxxxxxxxxx
Cc: Open Source Submission <patches@xxxxxxxxxxxxxxxxxxx>; Thang Q .
Nguyen <thang@xxxxxxxxxxxxxxxxxxxxxx>; Phong Vo
<phong@xxxxxxxxxxxxxxxxxxxxxx>; openbmc@xxxxxxxxxxxxxxxx
Subject: Re: [PATCH v3 5/7] i2c: aspeed: Add aspeed_set_slave_busy()
On 24/05/2021 17:06, Ryan Chen wrote:
-----Original Message-----
From: openbmc
<openbmc-bounces+ryan_chen=aspeedtech.com@xxxxxxxxxxxxxxxx> On
Behalf
Of Quan Nguyen
Sent: Wednesday, May 19, 2021 3:50 PM
To: Corey Minyard <minyard@xxxxxxx>; Rob Herring
<robh+dt@xxxxxxxxxx>; Joel Stanley <joel@xxxxxxxxx>; Andrew Jeffery
<andrew@xxxxxxxx>; Brendan Higgins <brendanhiggins@xxxxxxxxxx>;
Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>; Wolfram Sang
<wsa@xxxxxxxxxx>; Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>;
openipmi-developer@xxxxxxxxxxxxxxxxxxxxx;
devicetree@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
linux-aspeed@xxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
linux-i2c@xxxxxxxxxxxxxxx
Cc: Open Source Submission <patches@xxxxxxxxxxxxxxxxxxx>; Thang
Q .
Nguyen <thang@xxxxxxxxxxxxxxxxxxxxxx>; Phong Vo
<phong@xxxxxxxxxxxxxxxxxxxxxx>; openbmc@xxxxxxxxxxxxxxxx
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@xxxxxxxxxxxxxxxxxxxxxx>
---
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.
Yes, I see the probe function " ssif_bmc->priv =
i2c_get_adapdata(client->adapter);" to get priv.
But my question I don’t see the bus->base address be assigned.
Hi Ryan,
In drivers/i2c/busses/i2c-aspeed.c:
struct aspeed_i2c_bus {
struct i2c_adapter adap;
struct device *dev;
void __iomem *base;
struct reset_control *rst;
/* Synchronizes I/O mem access to base. */
spinlock_t lock;
So when "struct aspeed_i2c_bus *bus = i2c_get_adapdata(adap);", the
bus->base should point to the base of the aspeed_i2c_bus, which is
already initialized by the aspeed i2c bus driver.
Do I miss something?
Hello Quan,
After study. I think the ssif_bmc_aspeed.c assume the priv data is the same struct.
That is trick.
Do we have a better for slave enable/disable call back to implement this?
If add call back in struct i2c_algorithm; is it workable?
Hi Ryan,
I dont know which is better, ie: adding callback to struct i2c_algorithm
or to struct i2c_adapter.
I have tried to add generic callback to struct i2c_adapter as below and
it works.
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 4e7714c88f95..6e9abf2d6abb 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -713,6 +713,10 @@ struct i2c_adapter {
const struct i2c_adapter_quirks *quirks;
struct irq_domain *host_notify_domain;
+#if IS_ENABLED(CONFIG_I2C_SLAVE)
+ int (*slave_enable)(struct i2c_adapter *adap);
+ int (*slave_disable)(struct i2c_adapter *adap);
+#endif
};
#define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
+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