diff options
Diffstat (limited to 'target/linux/brcm2708/patches-4.4/0142-FIXUP-i2c_bcm2708-Don-t-change-module-baudrate-param.patch')
| -rw-r--r-- | target/linux/brcm2708/patches-4.4/0142-FIXUP-i2c_bcm2708-Don-t-change-module-baudrate-param.patch | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.4/0142-FIXUP-i2c_bcm2708-Don-t-change-module-baudrate-param.patch b/target/linux/brcm2708/patches-4.4/0142-FIXUP-i2c_bcm2708-Don-t-change-module-baudrate-param.patch new file mode 100644 index 0000000000..e2f4ba46ac --- /dev/null +++ b/target/linux/brcm2708/patches-4.4/0142-FIXUP-i2c_bcm2708-Don-t-change-module-baudrate-param.patch @@ -0,0 +1,99 @@ +From 3b0e6758d12a326405c257fe074dab570b1de92e Mon Sep 17 00:00:00 2001 +From: Phil Elwell <phil@raspberrypi.org> +Date: Tue, 19 Jan 2016 16:28:05 +0000 +Subject: [PATCH 142/156] FIXUP i2c_bcm2708: Don't change module baudrate + parameter + +Overwriting the baudrate module parameter creates an apparent +forced baudrate for i2c busses after the first. Not only does this +override the baudrate from DT it also prevents the bus ID from +being initialised. + +Also fix whitespace errors. +--- + drivers/i2c/busses/i2c-bcm2708.c | 48 +++++++++++++++++++++------------------- + 1 file changed, 25 insertions(+), 23 deletions(-) + +--- a/drivers/i2c/busses/i2c-bcm2708.c ++++ b/drivers/i2c/busses/i2c-bcm2708.c +@@ -71,7 +71,6 @@ + + #define DRV_NAME "bcm2708_i2c" + +-static unsigned int baudrate_default = CONFIG_I2C_BCM2708_BAUDRATE; + static unsigned int baudrate; + module_param(baudrate, uint, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP); + MODULE_PARM_DESC(baudrate, "The I2C baudrate"); +@@ -317,25 +316,28 @@ static int bcm2708_i2c_probe(struct plat + struct i2c_adapter *adap; + unsigned long bus_hz; + u32 cdiv, clk_tout; +- +- if (!baudrate) { +- baudrate = baudrate_default; +- if (pdev->dev.of_node) { +- u32 bus_clk_rate; +- pdev->id = of_alias_get_id(pdev->dev.of_node, "i2c"); +- if (pdev->id < 0) { +- dev_err(&pdev->dev, "alias is missing\n"); +- return -EINVAL; +- } +- if (!of_property_read_u32(pdev->dev.of_node, +- "clock-frequency", &bus_clk_rate)) +- baudrate = bus_clk_rate; +- else +- dev_warn(&pdev->dev, +- "Could not read clock-frequency property\n"); ++ u32 baud; ++ ++ baud = CONFIG_I2C_BCM2708_BAUDRATE; ++ ++ if (pdev->dev.of_node) { ++ u32 bus_clk_rate; ++ pdev->id = of_alias_get_id(pdev->dev.of_node, "i2c"); ++ if (pdev->id < 0) { ++ dev_err(&pdev->dev, "alias is missing\n"); ++ return -EINVAL; + } ++ if (!of_property_read_u32(pdev->dev.of_node, ++ "clock-frequency", &bus_clk_rate)) ++ baud = bus_clk_rate; ++ else ++ dev_warn(&pdev->dev, ++ "Could not read clock-frequency property\n"); + } + ++ if (baudrate) ++ baud = baudrate; ++ + regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!regs) { + dev_err(&pdev->dev, "could not get IO memory\n"); +@@ -419,21 +421,21 @@ static int bcm2708_i2c_probe(struct plat + } + + bus_hz = clk_get_rate(bi->clk); +- cdiv = bus_hz / baudrate; ++ cdiv = bus_hz / baud; + if (cdiv > 0xffff) { + cdiv = 0xffff; +- baudrate = bus_hz / cdiv; ++ baud = bus_hz / cdiv; + } +- +- clk_tout = 35/1000*baudrate; //35ms timeout as per SMBus specs. +- if (clk_tout > 0xffff) ++ ++ clk_tout = 35/1000*baud; //35ms timeout as per SMBus specs. ++ if (clk_tout > 0xffff) + clk_tout = 0xffff; + + bi->cdiv = cdiv; + bi->clk_tout = clk_tout; + + dev_info(&pdev->dev, "BSC%d Controller at 0x%08lx (irq %d) (baudrate %d)\n", +- pdev->id, (unsigned long)regs->start, irq, baudrate); ++ pdev->id, (unsigned long)regs->start, irq, baud); + + return 0; + |