Received-SPF: softfail (google.com: domain of transitioning linux-kernel-owner@vger.kernel.org does not designate 23.128.96.19 as permitted sender) client-ip=23.128.96.19;
From:   Quan Nguyen <quan@os.amperecomputing.com>
To:     Corey Minyard <minyard@acm.org>, Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>,
        Joel Stanley <joel@jms.id.au>,
        Andrew Jeffery <andrew@aj.id.au>,
        Brendan Higgins <brendanhiggins@google.com>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Wolfram Sang <wsa@kernel.org>,
        openipmi-developer@lists.sourceforge.net,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-aspeed@lists.ozlabs.org, linux-kernel@vger.kernel.org,
        linux-i2c@vger.kernel.org, openbmc@lists.ozlabs.org
Cc:     Open Source Submission <patches@amperecomputing.com>,
        Phong Vo <phong@os.amperecomputing.com>,
        "Thang Q . Nguyen" <thang@os.amperecomputing.com>
Subject: [PATCH v7 3/3] i2c: aspeed: Assert NAK when slave is busy
Date:   Fri, 22 Apr 2022 11:08:03 +0700
Message-Id: <20220422040803.2524940-4-quan@os.amperecomputing.com>
In-Reply-To: <20220422040803.2524940-1-quan@os.amperecomputing.com>
References: <20220422040803.2524940-1-quan@os.amperecomputing.com>
Content-Transfer-Encoding: 8bit
Content-Type: text/plain
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?KpbXOBUBjGfvhS9V6fFYD48P34937XU/+ZyEYrfIp5Tj59338/wiUQcMuC8o?=
 =?us-ascii?Q?nhRRZk9gOLNaYexvjSbGmR7QRRxetI3MdMcux6C0yhe0SymHBRsEgOIFnP55?=
 =?us-ascii?Q?9XjOOCQtGzr+hvvxjAJ0CXtosomZVm/iHVOMpF3MgljjQpbOGZEHgmF9KJOc?=
 =?us-ascii?Q?qHKKLWTsfflIEUcFOoYWayWTULfeeEHOZF3pAym6HljWGtuwjsBOJm/Y+woV?=
 =?us-ascii?Q?iLbMJXhTTslPqPE+0ytq5KO3REwY92f5KivHvZPJ27Sg0mE0T71xpjWuNpAu?=
 =?us-ascii?Q?W6BIjxatlEzp2hNp63qiWFCCxrHlT9Ychzrm+OcoKEiJosYGNOW1qYKXJZIw?=
 =?us-ascii?Q?p61F77CUmX3hj3Rpo8SAUimtmWf4bByLt9HBcpzRs/+mBJ3tdqIdSgcgUzma?=
 =?us-ascii?Q?nqjqQE5edFc1hG6mAAxLzYTNKvvNxMyqRLPYJQsyPutUph0z0LOfOs4SVltH?=
 =?us-ascii?Q?RdGkAggSM3mtFi0lxoalbCxamxpPljy17a7M2urJjYcMdES8H5NE+4hkZGOI?=
 =?us-ascii?Q?bWfMXOZ43vypnfKZUsbmhJwiRFsKnadiSQbDwWR8hG7pGrAkzxZi/jQxTp16?=
 =?us-ascii?Q?hhbIo+7OqDPzd8jxEUlQgmRuxQ4hMxNqj+zeO78B3C80rddtkyVcMh8ii14D?=
 =?us-ascii?Q?ZG1SiH7QbohhVFJoR165QD4QPplejyGL6kr+oKvTFrynKGHv7f64JPC97+ni?=
 =?us-ascii?Q?Kb0uOMB/8kZ0zcwTe3LUace1amcSvR9obIZPesERNabhX9WIQQLxVhgBZLiT?=
 =?us-ascii?Q?bprj3+R9KkIvGqg01+mrn7vFM0Omt7+5eN2mvEdPfl0XkIa7BwQmhCmrL7Q5?=
 =?us-ascii?Q?aT/zWT2YfvYJ4S7rzao+3a3egWhzU+3ZqsQPFnpuvvATe8bE6acbk6dDhPJj?=
 =?us-ascii?Q?nchyQk8W1mNzQAa298BA6DMg1a15ByP5wih3tCv2ZiPfdbpct92uC8TNoZcH?=
 =?us-ascii?Q?iqzzkfatQqLrbpWPnaGy2v0o3Izpohr54dO+CgjYa1blUNeZP7PnzlcD8Yg+?=
 =?us-ascii?Q?/5M2Xr7CZJlWfXqy2db6eAzlz1tLRBpZ8gFIu5SKoVlM+yr+8+pc4lGXuw92?=
 =?us-ascii?Q?sOwzP1yp22O09wFVVoNsDpAm8cpUZMy/0JdfFc3WTzWwCZPu9oJnySYz4A3a?=
 =?us-ascii?Q?p+05jKxZrZ8yIpap+In3NgzJV4kcpB8dfm98xezhxOerD+82rgrGv04ISwt2?=
 =?us-ascii?Q?YAEmGnuRcL8yMcnYkSMbxMsFmQX/6njOq/8BXt9Jg37nIcdbnaeKNgDJoOHA?=
 =?us-ascii?Q?ClYuOWZdnXqWbqfjfwpRys5SccL8ggDm8SQtvBQsyadRpFpV8VXBpuK1WJiz?=
 =?us-ascii?Q?GHFTc82YAt2WKUDqwZUt1fEpLRKkYVDJTNrdIMWFz34U3m+fuaFe2p+ZqJBQ?=
 =?us-ascii?Q?/CA3bc4B1DmDKVdL+NIIVbzOyOAeiEAkznY0P+9AuUfgi4tTIpu+4ubjZgpL?=
 =?us-ascii?Q?Plo83PtJVBcUBlA9WlN8qpTXMfYV0XgUxR6zslo5IyZPa99B3STvlE0EeSoR?=
 =?us-ascii?Q?jUlGDlpg9InFjkhV18Y4y/Q1+WpFHFWVfl4mcHHYIz3daKJpR+Ik0y/7hds/?=
 =?us-ascii?Q?BOo+/6r+1px4L4NzReN2v1szMXA0R6g8uJlDd723HFqz9CFFZUpwwzuGAJXY?=
 =?us-ascii?Q?VezJrdxY+3b359RHbawJnJ49yld+i9aVIvkKpe+ztiEqS1lSvP8xiTVTR6l4?=
 =?us-ascii?Q?wu4f7viEWhklTa8Xs0za9XREof/8jyCTgCi8jWJz0EeOQyU1SdrnH2u8Yp1+?=
 =?us-ascii?Q?SPGI4JC9TWJ2yL51YudshGX1g5NG8DXfsyVqOJSpX+A1aVVwBmFH?=
X-OriginatorOrg: os.amperecomputing.com
X-MS-Exchange-CrossTenant-Network-Message-Id: a60d5fe5-25f4-49dc-418c-08da2415c7cd
X-MS-Exchange-CrossTenant-AuthSource: SJ0PR01MB7282.prod.exchangelabs.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Apr 2022 04:08:39.6532
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 3bc2b170-fd94-476d-b0ce-4229bdc904a7
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: ndM1NHlCx66lE1qKY0ozIaQaKWFIn7Sr5LNHBC5+f4apwk1DTXYx30MdmjQ9ju0FOJa0iPqsk0IB15ny7VchImhoRVoYqv6ITrbk5SPaCpE=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL0PR0102MB3587
X-Spam-Status: No, score=-2.0 required=5.0 tests=BAYES_00,DKIM_SIGNED,
	DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,
	MAILING_LIST_MULTI,RDNS_NONE,SPF_HELO_NONE autolearn=no
	autolearn_force=no version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
	lindbergh.monkeyblade.net
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

When processing I2C_SLAVE_WRITE_REQUESTED event, if slave returns
-EBUSY, i2c controller should issue RxCmdLast command to assert NAK
on the bus.

Signed-off-by: Quan Nguyen <quan@os.amperecomputing.com>
---
v7:
  + None

v6:
  + New introduced in v6                      [Quan]

 drivers/i2c/busses/i2c-aspeed.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c
index 771e53d3d197..ebc2b92656c8 100644
--- a/drivers/i2c/busses/i2c-aspeed.c
+++ b/drivers/i2c/busses/i2c-aspeed.c
@@ -244,6 +244,7 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
 	u32 command, irq_handled = 0;
 	struct i2c_client *slave = bus->slave;
 	u8 value;
+	int ret;
 
 	if (!slave)
 		return 0;
@@ -311,7 +312,9 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
 		break;
 	case ASPEED_I2C_SLAVE_WRITE_REQUESTED:
 		bus->slave_state = ASPEED_I2C_SLAVE_WRITE_RECEIVED;
-		i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value);
+		ret = i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value);
+		if (ret == -EBUSY)
+			writel(ASPEED_I2CD_M_S_RX_CMD_LAST, bus->base + ASPEED_I2C_CMD_REG);
 		break;
 	case ASPEED_I2C_SLAVE_WRITE_RECEIVED:
 		i2c_slave_event(slave, I2C_SLAVE_WRITE_RECEIVED, &value);
-- 
2.35.1