lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <faf55447a1c9b72edb482bcb4fea1b1de3d50180.1509112910.git.me@jue.yt>
Date:   Fri, 27 Oct 2017 17:11:20 +0200
From:   Juergen Fitschen <me@....yt>
To:     Ludovic Desroches <ludovic.desroches@...rochip.com>,
        Wolfram Sang <wsa@...-dreams.de>, linux-i2c@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH RFC 1/4] i2c: at91: segregate master mode specific code from
 probe and init func

In order to implement slave mode support for the at91 hardware we have to
segregate all master mode specific function parts from the general parts.
The upcoming slave mode patch will call its sepcific probe resp. init
function instead of the master mode functions after the shared general
code has been executed.

This concept has been influenced by the i2c-designware driver.

Signed-off-by: Juergen Fitschen <me@....yt>
---
 drivers/i2c/busses/i2c-at91.c | 90 ++++++++++++++++++++++++++-----------------
 1 file changed, 55 insertions(+), 35 deletions(-)

diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index bfd1fdf..73b6582 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -174,10 +174,8 @@ static void at91_twi_irq_restore(struct at91_twi_dev *dev)
 	at91_twi_write(dev, AT91_TWI_IER, dev->imr);
 }
 
-static void at91_init_twi_bus(struct at91_twi_dev *dev)
+static void at91_init_twi_bus_master(struct at91_twi_dev *dev)
 {
-	at91_disable_twi_interrupts(dev);
-	at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_SWRST);
 	/* FIFO should be enabled immediately after the software reset */
 	if (dev->fifo_size)
 		at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_FIFOEN);
@@ -186,6 +184,14 @@ static void at91_init_twi_bus(struct at91_twi_dev *dev)
 	at91_twi_write(dev, AT91_TWI_CWGR, dev->twi_cwgr_reg);
 }
 
+static void at91_init_twi_bus(struct at91_twi_dev *dev)
+{
+	at91_disable_twi_interrupts(dev);
+	at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_SWRST);
+
+	at91_init_twi_bus_master(dev);
+}
+
 /*
  * Calculate symmetric clock as stated in datasheet:
  * twi_clk = F_MAIN / (2 * (cdiv * (1 << ckdiv) + offset))
@@ -1038,18 +1044,56 @@ static struct at91_twi_pdata *at91_twi_get_driver_data(
 	return (struct at91_twi_pdata *) platform_get_device_id(pdev)->driver_data;
 }
 
+static int at91_twi_probe_master(struct platform_device *pdev,
+				 u32 phy_addr, struct at91_twi_dev *dev)
+{
+	int rc;
+	u32 bus_clk_rate;
+
+	init_completion(&dev->cmd_complete);
+
+	rc = devm_request_irq(&pdev->dev, dev->irq, atmel_twi_interrupt, 0,
+			      dev_name(dev->dev), dev);
+	if (rc) {
+		dev_err(dev->dev, "Cannot get irq %d: %d\n", dev->irq, rc);
+		return rc;
+	}
+
+	if (dev->dev->of_node) {
+		rc = at91_twi_configure_dma(dev, phy_addr);
+		if (rc == -EPROBE_DEFER)
+			return rc;
+	}
+
+	if (!of_property_read_u32(pdev->dev.of_node, "atmel,fifo-size",
+				  &dev->fifo_size)) {
+		dev_info(dev->dev, "Using FIFO (%u data)\n", dev->fifo_size);
+	}
+
+	rc = of_property_read_u32(dev->dev->of_node, "clock-frequency",
+				  &bus_clk_rate);
+	if (rc)
+		bus_clk_rate = DEFAULT_TWI_CLK_HZ;
+
+	at91_calc_twi_clock(dev, bus_clk_rate);
+
+	dev->adapter.algo = &at91_twi_algorithm;
+	dev->adapter.quirks = &at91_twi_quirks;
+
+	return 0;
+}
+
 static int at91_twi_probe(struct platform_device *pdev)
 {
 	struct at91_twi_dev *dev;
 	struct resource *mem;
 	int rc;
 	u32 phy_addr;
-	u32 bus_clk_rate;
 
 	dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
 	if (!dev)
 		return -ENOMEM;
-	init_completion(&dev->cmd_complete);
+
 	dev->dev = &pdev->dev;
 
 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -1069,13 +1113,6 @@ static int at91_twi_probe(struct platform_device *pdev)
 	if (dev->irq < 0)
 		return dev->irq;
 
-	rc = devm_request_irq(&pdev->dev, dev->irq, atmel_twi_interrupt, 0,
-			 dev_name(dev->dev), dev);
-	if (rc) {
-		dev_err(dev->dev, "Cannot get irq %d: %d\n", dev->irq, rc);
-		return rc;
-	}
-
 	platform_set_drvdata(pdev, dev);
 
 	dev->clk = devm_clk_get(dev->dev, NULL);
@@ -1087,38 +1124,21 @@ static int at91_twi_probe(struct platform_device *pdev)
 	if (rc)
 		return rc;
 
-	if (dev->dev->of_node) {
-		rc = at91_twi_configure_dma(dev, phy_addr);
-		if (rc == -EPROBE_DEFER) {
-			clk_disable_unprepare(dev->clk);
-			return rc;
-		}
-	}
-
-	if (!of_property_read_u32(pdev->dev.of_node, "atmel,fifo-size",
-				  &dev->fifo_size)) {
-		dev_info(dev->dev, "Using FIFO (%u data)\n", dev->fifo_size);
-	}
-
-	rc = of_property_read_u32(dev->dev->of_node, "clock-frequency",
-			&bus_clk_rate);
-	if (rc)
-		bus_clk_rate = DEFAULT_TWI_CLK_HZ;
-
-	at91_calc_twi_clock(dev, bus_clk_rate);
-	at91_init_twi_bus(dev);
-
 	snprintf(dev->adapter.name, sizeof(dev->adapter.name), "AT91");
 	i2c_set_adapdata(&dev->adapter, dev);
 	dev->adapter.owner = THIS_MODULE;
 	dev->adapter.class = I2C_CLASS_DEPRECATED;
-	dev->adapter.algo = &at91_twi_algorithm;
-	dev->adapter.quirks = &at91_twi_quirks;
 	dev->adapter.dev.parent = dev->dev;
 	dev->adapter.nr = pdev->id;
 	dev->adapter.timeout = AT91_I2C_TIMEOUT;
 	dev->adapter.dev.of_node = pdev->dev.of_node;
 
+	rc = at91_twi_probe_master(pdev, phy_addr, dev);
+	if (rc)
+		return rc;
+
+	at91_init_twi_bus(dev);
+
 	pm_runtime_set_autosuspend_delay(dev->dev, AUTOSUSPEND_TIMEOUT);
 	pm_runtime_use_autosuspend(dev->dev);
 	pm_runtime_set_active(dev->dev);
-- 
2.7.4

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ