From patchwork Sun Apr 27 11:30:45 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sven Peter via B4 Relay X-Patchwork-Id: 885365 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 25AAB17A2F0; Sun, 27 Apr 2025 11:31:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745753466; cv=none; b=h7sTSrj94DaTY2o+gxFeXr6llk3YJvHvmmcopQ6tSKHxae0QOgtx0XGgRVgF4tER8nUQzKmC45D8z4MDDix7rxUEYXpKgs3Ko5tE0QIIZk57cM63VdFO4rFurPkOHJgEqCaGGZOcdS4gom4njPkpzyBgz3HJ3WS3jwaVHhtm0mI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745753466; c=relaxed/simple; bh=nYEoUAOYWWe1YgrKh5F/Uu0ClKx/Vy3NGeA0qWcOwyo=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=q9ytfxZHvPv9ksS/2TNbR20HCPjSrGXyZgCDWO30LBM6nh39gWpsII/qhjGDlZDWgLQvecFyBmxcqZJuA9bbIffAyNbT0wVkkDlEeWwOQygZlPwJGt6yD9Qg+jEn/sDpvcci7heAa/+oYsY0KGbx0UCJhxCCk30EH5nKC0jvXjQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=DmqObJfS; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="DmqObJfS" Received: by smtp.kernel.org (Postfix) with ESMTPS id B0FDFC4CEEF; Sun, 27 Apr 2025 11:31:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1745753465; bh=nYEoUAOYWWe1YgrKh5F/Uu0ClKx/Vy3NGeA0qWcOwyo=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=DmqObJfSjvkHnlkZgErAaxvRjqcppPchhkfMe39U+sJFKtK5w4iCL7c9x6ObknXww EicxT+HQ6/5+hvieORhsBZ6VkeAvE3cmMVSuS2BYhziV6O6weI/d1fVTmQbwz70NLE 48vX687s1P/ix4xLr1DYmXYTHIISIgTCdOyEDHiKA4B3doVmScS2ZGfQ6y2sUtw3V/ 78HZvxM1AKJAblOgIsDdd72L8pp8ajiZArUk280ziOa8+71GyXLwYDvDeLq+YLX4td iWjkjoxF8OsQAUcXmLzqSigRYE6rzwfbrj2ozFVFlSEJzHiUr+D4NWPRvOIlyXDA+a gF8cpNsXhjBew== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id A4935C369D1; Sun, 27 Apr 2025 11:31:05 +0000 (UTC) From: Sven Peter via B4 Relay Date: Sun, 27 Apr 2025 11:30:45 +0000 Subject: [PATCH v3 3/4] i2c: pasemi: Improve error recovery Precedence: bulk X-Mailing-List: linux-i2c@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20250427-pasemi-fixes-v3-3-af28568296c0@svenpeter.dev> References: <20250427-pasemi-fixes-v3-0-af28568296c0@svenpeter.dev> In-Reply-To: <20250427-pasemi-fixes-v3-0-af28568296c0@svenpeter.dev> To: Janne Grunau , Alyssa Rosenzweig , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Naveen N Rao , Andi Shyti , Neal Gompa , Hector Martin Cc: linuxppc-dev@lists.ozlabs.org, asahi@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, Sven Peter X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=3408; i=sven@svenpeter.dev; h=from:subject:message-id; bh=RQjUShH7rfus6djDqHEQgJ89KeDc5Vm8l5ffHfaOO3w=; b=owGbwMvMwCHmIlirolUq95LxtFoSQwafaCnnKomj7TVR2fJPP2nrKIu1nnmY/XB6sRmL7W2Gl TN/u3zrKGVhEONgkBVTZNm+3970ycM3gks3XXoPM4eVCWQIAxenAExk4wNGhrVvj6W+rlAuuXsr W8ns8tK0Hf2G+9n57Wq43vz8EOrK8Jjhf+CO+N5Tsxav/3Hhxfn8aVvfMWhIvs189/nVKb4s3op 3F3kA X-Developer-Key: i=sven@svenpeter.dev; a=openpgp; fpr=A1E3E34A2B3C820DBC4955E5993B08092F131F93 X-Endpoint-Received: by B4 Relay for sven@svenpeter.dev/default with auth_id=167 X-Original-From: Sven Peter Reply-To: sven@svenpeter.dev From: Hector Martin Add handling for all the missing error condition, and better recovery in pasemi_smb_clear(). Reviewed-by: Alyssa Rosenzweig Reviewed-by: Neal Gompa Signed-off-by: Hector Martin Co-developed-by: Sven Peter Signed-off-by: Sven Peter --- drivers/i2c/busses/i2c-pasemi-core.c | 61 +++++++++++++++++++++++++++++++----- 1 file changed, 54 insertions(+), 7 deletions(-) diff --git a/drivers/i2c/busses/i2c-pasemi-core.c b/drivers/i2c/busses/i2c-pasemi-core.c index ee38e8a1e1f5d062384e85a2fd49d7da9257aacc..dad20ee0c6689eda309cb0374aa75b42669cbcdc 100644 --- a/drivers/i2c/busses/i2c-pasemi-core.c +++ b/drivers/i2c/busses/i2c-pasemi-core.c @@ -87,12 +87,31 @@ static void pasemi_reset(struct pasemi_smbus *smbus) reinit_completion(&smbus->irq_completion); } -static void pasemi_smb_clear(struct pasemi_smbus *smbus) +static int pasemi_smb_clear(struct pasemi_smbus *smbus) { unsigned int status; + int ret; - status = reg_read(smbus, REG_SMSTA); + /* First wait for the bus to go idle */ + ret = readx_poll_timeout(ioread32, smbus->ioaddr + REG_SMSTA, + status, !(status & (SMSTA_XIP | SMSTA_JAM)), + USEC_PER_MSEC, + USEC_PER_MSEC * PASEMI_TRANSFER_TIMEOUT_MS); + + if (ret < 0) { + dev_err(smbus->dev, "Bus is still stuck (status 0x%08x)\n", status); + return -EIO; + } + + /* If any badness happened or there is data in the FIFOs, reset the FIFOs */ + if ((status & (SMSTA_MRNE | SMSTA_JMD | SMSTA_MTO | SMSTA_TOM | SMSTA_MTN | SMSTA_MTA)) || + !(status & SMSTA_MTE)) + pasemi_reset(smbus); + + /* Clear the flags */ reg_write(smbus, REG_SMSTA, status); + + return 0; } static int pasemi_smb_waitready(struct pasemi_smbus *smbus) @@ -130,9 +149,35 @@ static int pasemi_smb_waitready(struct pasemi_smbus *smbus) } } + /* Controller timeout? */ + if (status & SMSTA_TOM) { + dev_err(smbus->dev, "Controller timeout, status 0x%08x\n", status); + return -EIO; + } + + /* Peripheral timeout? */ + if (status & SMSTA_MTO) { + dev_err(smbus->dev, "Peripheral timeout, status 0x%08x\n", status); + return -ETIME; + } + + /* Still stuck in a transaction? */ + if (status & SMSTA_XIP) { + dev_err(smbus->dev, "Bus stuck, status 0x%08x\n", status); + return -EIO; + } + + /* Arbitration loss? */ + if (status & SMSTA_MTA) { + dev_err(smbus->dev, "Arbitration loss, status 0x%08x\n", status); + return -EBUSY; + } + /* Got NACK? */ - if (status & SMSTA_MTN) + if (status & SMSTA_MTN) { + dev_err(smbus->dev, "NACK, status 0x%08x\n", status); return -ENXIO; + } /* Clear XEN */ reg_write(smbus, REG_SMSTA, SMSTA_XEN); @@ -194,9 +239,9 @@ static int pasemi_i2c_xfer(struct i2c_adapter *adapter, struct pasemi_smbus *smbus = adapter->algo_data; int ret, i; - pasemi_smb_clear(smbus); - - ret = 0; + ret = pasemi_smb_clear(smbus); + if (ret) + return ret; for (i = 0; i < num && !ret; i++) ret = pasemi_i2c_xfer_msg(adapter, &msgs[i], (i == (num - 1))); @@ -217,7 +262,9 @@ static int pasemi_smb_xfer(struct i2c_adapter *adapter, addr <<= 1; read_flag = read_write == I2C_SMBUS_READ; - pasemi_smb_clear(smbus); + err = pasemi_smb_clear(smbus); + if (err) + return err; switch (size) { case I2C_SMBUS_QUICK: