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From:   Cai Huoqing <cai.huoqing@linux.dev>
To:     cai.huoqing@linux.dev
Cc:     Sanjay R Mehta <sanju.mehta@amd.com>,
        Shyam Sundar S K <Shyam-sundar.S-k@amd.com>,
        Jon Mason <jdmason@kudzu.us>,
        Dave Jiang <dave.jiang@intel.com>,
        Allen Hubbe <allenbh@gmail.com>, Frank Li <Frank.Li@nxp.com>,
        ntb@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: [PATCH 1/3] ntb_hw_amd: Remove redundant pci_clear_master
Date:   Thu, 23 Mar 2023 19:53:33 +0800
Message-Id: <20230323115336.12986-1-cai.huoqing@linux.dev>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Remove pci_clear_master to simplify the code,
the bus-mastering is also cleared in do_pci_disable_device,
like this:
./drivers/pci/pci.c:2197
static void do_pci_disable_device(struct pci_dev *dev)
{
	u16 pci_command;

	pci_read_config_word(dev, PCI_COMMAND, &pci_command);
	if (pci_command & PCI_COMMAND_MASTER) {
		pci_command &= ~PCI_COMMAND_MASTER;
		pci_write_config_word(dev, PCI_COMMAND, pci_command);
	}

	pcibios_disable_device(dev);
}.
And dev->is_busmaster is set to 0 in pci_disable_device.

Signed-off-by: Cai Huoqing <cai.huoqing@linux.dev>
---
 drivers/ntb/hw/amd/ntb_hw_amd.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/ntb/hw/amd/ntb_hw_amd.c b/drivers/ntb/hw/amd/ntb_hw_amd.c
index 730f2103b91d..855ff65f64a5 100644
--- a/drivers/ntb/hw/amd/ntb_hw_amd.c
+++ b/drivers/ntb/hw/amd/ntb_hw_amd.c
@@ -1194,7 +1194,6 @@ static int amd_ntb_init_pci(struct amd_ntb_dev *ndev,
 	return 0;
 
 err_dma_mask:
-	pci_clear_master(pdev);
 	pci_release_regions(pdev);
 err_pci_regions:
 	pci_disable_device(pdev);
@@ -1209,7 +1208,6 @@ static void amd_ntb_deinit_pci(struct amd_ntb_dev *ndev)
 
 	pci_iounmap(pdev, ndev->self_mmio);
 
-	pci_clear_master(pdev);
 	pci_release_regions(pdev);
 	pci_disable_device(pdev);
 	pci_set_drvdata(pdev, NULL);
-- 
2.34.1