Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa...

Pull i2c fixes from Wolfram Sang:
 "I2C has one revert because of a regression, two fixes for tiny race
  windows (which we were not able to trigger), a MAINTAINERS addition,
  and a SPDX fix"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: stm32: Use the correct style for SPDX License Identifier
  i2c: emev2: avoid race when unregistering slave client
  i2c: rcar: avoid race when unregistering slave client
  MAINTAINERS: i2c-imx: take over maintainership
  Revert "i2c: imx: improve the error handling in i2c_imx_dma_request()"

diff --git a/MAINTAINERS b/MAINTAINERS
index 997a4f8..14dc542 100644 (file)
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6441,6 +6441,14 @@ S:       Maintained
 F:     drivers/perf/fsl_imx8_ddr_perf.c
 F:     Documentation/devicetree/bindings/perf/fsl-imx-ddr.txt
 
+FREESCALE IMX I2C DRIVER
+M:     Oleksij Rempel <o.rempel@pengutronix.de>
+R:     Pengutronix Kernel Team <kernel@pengutronix.de>
+L:     linux-i2c@vger.kernel.org
+S:     Maintained
+F:     drivers/i2c/busses/i2c-imx.c
+F:     Documentation/devicetree/bindings/i2c/i2c-imx.txt
+
 FREESCALE IMX LPI2C DRIVER
 M:     Dong Aisheng <aisheng.dong@nxp.com>
 L:     linux-i2c@vger.kernel.org

diff --git a/drivers/i2c/busses/i2c-emev2.c b/drivers/i2c/busses/i2c-emev2.c
index 35b302d..959d491 100644 (file)
--- a/drivers/i2c/busses/i2c-emev2.c
+++ b/drivers/i2c/busses/i2c-emev2.c
@@ -69,6 +69,7 @@ struct em_i2c_device {
        struct completion msg_done;
        struct clk *sclk;
        struct i2c_client *slave;
+       int irq;
 };
 
 static inline void em_clear_set_bit(struct em_i2c_device *priv, u8 clear, u8 set, u8 reg)
@@ -339,6 +340,12 @@ static int em_i2c_unreg_slave(struct i2c_client *slave)
 
        writeb(0, priv->base + I2C_OFS_SVA0);
 
+       /*
+        * Wait for interrupt to finish. New slave irqs cannot happen because we
+        * cleared the slave address and, thus, only extension codes will be
+        * detected which do not use the slave ptr.
+        */
+       synchronize_irq(priv->irq);
        priv->slave = NULL;
 
        return 0;
@@ -355,7 +362,7 @@ static int em_i2c_probe(struct platform_device *pdev)
 {
        struct em_i2c_device *priv;
        struct resource *r;
-       int irq, ret;
+       int ret;
 
        priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
        if (!priv)
@@ -390,8 +397,8 @@ static int em_i2c_probe(struct platform_device *pdev)
 
        em_i2c_reset(&priv->adap);
 
-       irq = platform_get_irq(pdev, 0);
-       ret = devm_request_irq(&pdev->dev, irq, em_i2c_irq_handler, 0,
+       priv->irq = platform_get_irq(pdev, 0);
+       ret = devm_request_irq(&pdev->dev, priv->irq, em_i2c_irq_handler, 0,
                                "em_i2c", priv);
        if (ret)
                goto err_clk;
@@ -401,7 +408,8 @@ static int em_i2c_probe(struct platform_device *pdev)
        if (ret)
                goto err_clk;
 
-       dev_info(&pdev->dev, "Added i2c controller %d, irq %d\n", priv->adap.nr, irq);
+       dev_info(&pdev->dev, "Added i2c controller %d, irq %d\n", priv->adap.nr,
+                priv->irq);
 
        return 0;
 

diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index b1b8b93..15f6cde 100644 (file)
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -273,8 +273,8 @@ static inline unsigned char imx_i2c_read_reg(struct imx_i2c_struct *i2c_imx,
 }
 
 /* Functions for DMA support */
-static int i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx,
-                              dma_addr_t phy_addr)
+static void i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx,
+                                               dma_addr_t phy_addr)
 {
        struct imx_i2c_dma *dma;
        struct dma_slave_config dma_sconfig;
@@ -283,7 +283,7 @@ static int i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx,
 
        dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
        if (!dma)
-               return -ENOMEM;
+               return;
 
        dma->chan_tx = dma_request_chan(dev, "tx");
        if (IS_ERR(dma->chan_tx)) {
@@ -328,7 +328,7 @@ static int i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx,
        dev_info(dev, "using %s (tx) and %s (rx) for DMA transfers\n",
                dma_chan_name(dma->chan_tx), dma_chan_name(dma->chan_rx));
 
-       return 0;
+       return;
 
 fail_rx:
        dma_release_channel(dma->chan_rx);
@@ -336,8 +336,6 @@ fail_tx:
        dma_release_channel(dma->chan_tx);
 fail_al:
        devm_kfree(dev, dma);
-       /* return successfully if there is no dma support */
-       return ret == -ENODEV ? 0 : ret;
 }
 
 static void i2c_imx_dma_callback(void *arg)
@@ -1165,17 +1163,13 @@ static int i2c_imx_probe(struct platform_device *pdev)
        dev_dbg(&i2c_imx->adapter.dev, "device resources: %pR\n", res);
        dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n",
                i2c_imx->adapter.name);
+       dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
 
        /* Init DMA config if supported */
-       ret = i2c_imx_dma_request(i2c_imx, phy_addr);
-       if (ret < 0)
-               goto del_adapter;
+       i2c_imx_dma_request(i2c_imx, phy_addr);
 
-       dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
        return 0;   /* Return OK */
 
-del_adapter:
-       i2c_del_adapter(&i2c_imx->adapter);
 clk_notifier_unregister:
        clk_notifier_unregister(i2c_imx->clk, &i2c_imx->clk_change_nb);
 rpm_disable:

diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c
index d39a460..531c011 100644 (file)
--- a/drivers/i2c/busses/i2c-rcar.c
+++ b/drivers/i2c/busses/i2c-rcar.c
@@ -139,6 +139,7 @@ struct rcar_i2c_priv {
        enum dma_data_direction dma_direction;
 
        struct reset_control *rstc;
+       int irq;
 };
 
 #define rcar_i2c_priv_to_dev(p)                ((p)->adap.dev.parent)
@@ -861,9 +862,11 @@ static int rcar_unreg_slave(struct i2c_client *slave)
 
        WARN_ON(!priv->slave);
 
+       /* disable irqs and ensure none is running before clearing ptr */
        rcar_i2c_write(priv, ICSIER, 0);
        rcar_i2c_write(priv, ICSCR, 0);
 
+       synchronize_irq(priv->irq);
        priv->slave = NULL;
 
        pm_runtime_put(rcar_i2c_priv_to_dev(priv));
@@ -918,7 +921,7 @@ static int rcar_i2c_probe(struct platform_device *pdev)
        struct i2c_adapter *adap;
        struct device *dev = &pdev->dev;
        struct i2c_timings i2c_t;
-       int irq, ret;
+       int ret;
 
        /* Otherwise logic will break because some bytes must always use PIO */
        BUILD_BUG_ON_MSG(RCAR_MIN_DMA_LEN < 3, "Invalid min DMA length");
@@ -984,10 +987,10 @@ static int rcar_i2c_probe(struct platform_device *pdev)
                pm_runtime_put(dev);
 
 
-       irq = platform_get_irq(pdev, 0);
-       ret = devm_request_irq(dev, irq, rcar_i2c_irq, 0, dev_name(dev), priv);
+       priv->irq = platform_get_irq(pdev, 0);
+       ret = devm_request_irq(dev, priv->irq, rcar_i2c_irq, 0, dev_name(dev), priv);
        if (ret < 0) {
-               dev_err(dev, "cannot get irq %d\n", irq);
+               dev_err(dev, "cannot get irq %d\n", priv->irq);
                goto out_pm_disable;
        }
 

diff --git a/drivers/i2c/busses/i2c-stm32.h b/drivers/i2c/busses/i2c-stm32.h
index 868755f..2c21893 100644 (file)
--- a/drivers/i2c/busses/i2c-stm32.h
+++ b/drivers/i2c/busses/i2c-stm32.h
@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: GPL-2.0
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * i2c-stm32.h
  *