diff options
Diffstat (limited to 'target/linux/brcm2708/patches-4.1/0020-Add-Chris-Boot-s-i2c-driver.patch')
| -rw-r--r-- | target/linux/brcm2708/patches-4.1/0020-Add-Chris-Boot-s-i2c-driver.patch | 792 |
1 files changed, 792 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.1/0020-Add-Chris-Boot-s-i2c-driver.patch b/target/linux/brcm2708/patches-4.1/0020-Add-Chris-Boot-s-i2c-driver.patch new file mode 100644 index 0000000..c596724 --- /dev/null +++ b/target/linux/brcm2708/patches-4.1/0020-Add-Chris-Boot-s-i2c-driver.patch @@ -0,0 +1,792 @@ +From 31dade83cc4f448f81d7d460c59d02b9ebc3b05b Mon Sep 17 00:00:00 2001 +From: popcornmix <popcornmix@gmail.com> +Date: Wed, 17 Jun 2015 15:44:08 +0100 +Subject: [PATCH 020/121] Add Chris Boot's i2c driver + +i2c-bcm2708: fixed baudrate + +Fixed issue where the wrong CDIV value was set for baudrates below 3815 Hz (for 250MHz bus clock). +In that case the computed CDIV value was more than 0xffff. However the CDIV register width is only 16 bits. +This resulted in incorrect setting of CDIV and higher baudrate than intended. +Example: 3500Hz -> CDIV=0x11704 -> CDIV(16bit)=0x1704 -> 42430Hz +After correction: 3500Hz -> CDIV=0x11704 -> CDIV(16bit)=0xffff -> 3815Hz +The correct baudrate is shown in the log after the cdiv > 0xffff correction. + +Perform I2C combined transactions when possible + +Perform I2C combined transactions whenever possible, within the +restrictions of the Broadcomm Serial Controller. + +Disable DONE interrupt during TA poll + +Prevent interrupt from being triggered if poll is missed and transfer +starts and finishes. + +i2c: Make combined transactions optional and disabled by default + +i2c: bcm2708: add device tree support + +Add DT support to driver and add to .dtsi file. +Setup pins in .dts file. +i2c is disabled by default. + +Signed-off-by: Noralf Tronnes <notro@tronnes.org> + +bcm2708: don't register i2c controllers when using DT + +The devices for the i2c controllers are in the Device Tree. +Only register devices when not using DT. + +Signed-off-by: Noralf Tronnes <notro@tronnes.org> + +I2C: Only register the I2C device for the current board revision + +i2c_bcm2708: Fix clock reference counting + +Fix grabbing lock from atomic context in i2c driver + +2 main changes: +- check for timeouts in the bcm2708_bsc_setup function as indicated by this comment: + /* poll for transfer start bit (should only take 1-20 polls) */ + This implies that the setup function can now fail so account for this everywhere it's called +- Removed the clk_get_rate call from inside the setup function as it locks a mutex and that's not ok since we call it from under a spin lock. + +i2c-bcm2708: When using DT, leave the GPIO setup to pinctrl +--- + arch/arm/mach-bcm2708/bcm2708.c | 51 ++++ + arch/arm/mach-bcm2709/bcm2709.c | 51 ++++ + drivers/i2c/busses/Kconfig | 21 +- + drivers/i2c/busses/Makefile | 2 + + drivers/i2c/busses/i2c-bcm2708.c | 522 +++++++++++++++++++++++++++++++++++++++ + 5 files changed, 646 insertions(+), 1 deletion(-) + create mode 100644 drivers/i2c/busses/i2c-bcm2708.c + +--- a/arch/arm/mach-bcm2708/bcm2708.c ++++ b/arch/arm/mach-bcm2708/bcm2708.c +@@ -83,6 +83,7 @@ static unsigned uart_clock = UART0_CLOCK + static unsigned disk_led_gpio = 16; + static unsigned disk_led_active_low = 1; + static unsigned reboot_part = 0; ++static bool vc_i2c_override = false; + + static unsigned use_dt = 0; + +@@ -550,6 +551,45 @@ static struct spi_board_info bcm2708_spi + }; + #endif + ++static struct resource bcm2708_bsc0_resources[] = { ++ { ++ .start = BSC0_BASE, ++ .end = BSC0_BASE + SZ_256 - 1, ++ .flags = IORESOURCE_MEM, ++ }, { ++ .start = INTERRUPT_I2C, ++ .end = INTERRUPT_I2C, ++ .flags = IORESOURCE_IRQ, ++ } ++}; ++ ++static struct platform_device bcm2708_bsc0_device = { ++ .name = "bcm2708_i2c", ++ .id = 0, ++ .num_resources = ARRAY_SIZE(bcm2708_bsc0_resources), ++ .resource = bcm2708_bsc0_resources, ++}; ++ ++ ++static struct resource bcm2708_bsc1_resources[] = { ++ { ++ .start = BSC1_BASE, ++ .end = BSC1_BASE + SZ_256 - 1, ++ .flags = IORESOURCE_MEM, ++ }, { ++ .start = INTERRUPT_I2C, ++ .end = INTERRUPT_I2C, ++ .flags = IORESOURCE_IRQ, ++ } ++}; ++ ++static struct platform_device bcm2708_bsc1_device = { ++ .name = "bcm2708_i2c", ++ .id = 1, ++ .num_resources = ARRAY_SIZE(bcm2708_bsc1_resources), ++ .resource = bcm2708_bsc1_resources, ++}; ++ + static struct platform_device bcm2835_thermal_device = { + .name = "bcm2835_thermal", + }; +@@ -702,6 +742,15 @@ void __init bcm2708_init(void) + + bcm_register_device_dt(&bcm2708_spi_device); + ++ if (vc_i2c_override) { ++ bcm_register_device_dt(&bcm2708_bsc0_device); ++ bcm_register_device_dt(&bcm2708_bsc1_device); ++ } else if ((boardrev & 0xffffff) == 0x2 || (boardrev & 0xffffff) == 0x3) { ++ bcm_register_device_dt(&bcm2708_bsc0_device); ++ } else { ++ bcm_register_device_dt(&bcm2708_bsc1_device); ++ } ++ + bcm_register_device_dt(&bcm2835_thermal_device); + + if (!use_dt) { +@@ -893,3 +942,5 @@ module_param(uart_clock, uint, 0644); + module_param(disk_led_gpio, uint, 0644); + module_param(disk_led_active_low, uint, 0644); + module_param(reboot_part, uint, 0644); ++module_param(vc_i2c_override, bool, 0644); ++MODULE_PARM_DESC(vc_i2c_override, "Allow the use of VC's I2C peripheral."); +--- a/arch/arm/mach-bcm2709/bcm2709.c ++++ b/arch/arm/mach-bcm2709/bcm2709.c +@@ -85,6 +85,7 @@ static unsigned uart_clock = UART0_CLOCK + static unsigned disk_led_gpio = 16; + static unsigned disk_led_active_low = 1; + static unsigned reboot_part = 0; ++static bool vc_i2c_override = false; + + static unsigned use_dt = 0; + +@@ -570,6 +571,45 @@ static struct spi_board_info bcm2708_spi + }; + #endif + ++static struct resource bcm2708_bsc0_resources[] = { ++ { ++ .start = BSC0_BASE, ++ .end = BSC0_BASE + SZ_256 - 1, ++ .flags = IORESOURCE_MEM, ++ }, { ++ .start = INTERRUPT_I2C, ++ .end = INTERRUPT_I2C, ++ .flags = IORESOURCE_IRQ, ++ } ++}; ++ ++static struct platform_device bcm2708_bsc0_device = { ++ .name = "bcm2708_i2c", ++ .id = 0, ++ .num_resources = ARRAY_SIZE(bcm2708_bsc0_resources), ++ .resource = bcm2708_bsc0_resources, ++}; ++ ++ ++static struct resource bcm2708_bsc1_resources[] = { ++ { ++ .start = BSC1_BASE, ++ .end = BSC1_BASE + SZ_256 - 1, ++ .flags = IORESOURCE_MEM, ++ }, { ++ .start = INTERRUPT_I2C, ++ .end = INTERRUPT_I2C, ++ .flags = IORESOURCE_IRQ, ++ } ++}; ++ ++static struct platform_device bcm2708_bsc1_device = { ++ .name = "bcm2708_i2c", ++ .id = 1, ++ .num_resources = ARRAY_SIZE(bcm2708_bsc1_resources), ++ .resource = bcm2708_bsc1_resources, ++}; ++ + static struct platform_device bcm2835_thermal_device = { + .name = "bcm2835_thermal", + }; +@@ -722,6 +762,15 @@ void __init bcm2709_init(void) + + bcm_register_device_dt(&bcm2708_spi_device); + ++ if (vc_i2c_override) { ++ bcm_register_device_dt(&bcm2708_bsc0_device); ++ bcm_register_device_dt(&bcm2708_bsc1_device); ++ } else if ((boardrev & 0xffffff) == 0x2 || (boardrev & 0xffffff) == 0x3) { ++ bcm_register_device_dt(&bcm2708_bsc0_device); ++ } else { ++ bcm_register_device_dt(&bcm2708_bsc1_device); ++ } ++ + bcm_register_device_dt(&bcm2835_thermal_device); + + if (!use_dt) { +@@ -1061,3 +1110,5 @@ module_param(uart_clock, uint, 0644); + module_param(disk_led_gpio, uint, 0644); + module_param(disk_led_active_low, uint, 0644); + module_param(reboot_part, uint, 0644); ++module_param(vc_i2c_override, bool, 0644); ++MODULE_PARM_DESC(vc_i2c_override, "Allow the use of VC's I2C peripheral."); +--- a/drivers/i2c/busses/Kconfig ++++ b/drivers/i2c/busses/Kconfig +@@ -8,6 +8,25 @@ menu "I2C Hardware Bus support" + comment "PC SMBus host controller drivers" + depends on PCI + ++config I2C_BCM2708 ++ tristate "BCM2708 BSC" ++ depends on MACH_BCM2708 || MACH_BCM2709 ++ help ++ Enabling this option will add BSC (Broadcom Serial Controller) ++ support for the BCM2708. BSC is a Broadcom proprietary bus compatible ++ with I2C/TWI/SMBus. ++ ++config I2C_BCM2708_BAUDRATE ++ prompt "BCM2708 I2C baudrate" ++ depends on I2C_BCM2708 ++ int ++ default 100000 ++ help ++ Set the I2C baudrate. This will alter the default value. A ++ different baudrate can be set by using a module parameter as well. If ++ no parameter is provided when loading, this is the value that will be ++ used. ++ + config I2C_ALI1535 + tristate "ALI 1535" + depends on PCI +@@ -362,7 +381,7 @@ config I2C_AXXIA + + config I2C_BCM2835 + tristate "Broadcom BCM2835 I2C controller" +- depends on ARCH_BCM2835 ++ depends on ARCH_BCM2835 || ARCH_BCM2708 || ARCH_BCM2709 + help + If you say yes to this option, support will be included for the + BCM2835 I2C controller. +--- a/drivers/i2c/busses/Makefile ++++ b/drivers/i2c/busses/Makefile +@@ -2,6 +2,8 @@ + # Makefile for the i2c bus drivers. + # + ++obj-$(CONFIG_I2C_BCM2708) += i2c-bcm2708.o ++ + # ACPI drivers + obj-$(CONFIG_I2C_SCMI) += i2c-scmi.o + +--- /dev/null ++++ b/drivers/i2c/busses/i2c-bcm2708.c +@@ -0,0 +1,522 @@ ++/* ++ * Driver for Broadcom BCM2708 BSC Controllers ++ * ++ * Copyright (C) 2012 Chris Boot & Frank Buss ++ * ++ * This driver is inspired by: ++ * i2c-ocores.c, by Peter Korsgaard <jacmet@sunsite.dk> ++ * ++ * This program is free software; you can redistribute it and/or modify ++ * it under the terms of the GNU General Public License as published by ++ * the Free Software Foundation; either version 2 of the License, or ++ * (at your option) any later version. ++ * ++ * This program is distributed in the hope that it will be useful, ++ * but WITHOUT ANY WARRANTY; without even the implied warranty of ++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ++ * GNU General Public License for more details. ++ * ++ * You should have received a copy of the GNU General Public License ++ * along with this program; if not, write to the Free Software ++ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. ++ */ ++ ++#include <linux/kernel.h> ++#include <linux/module.h> ++#include <linux/spinlock.h> ++#include <linux/clk.h> ++#include <linux/err.h> ++#include <linux/of.h> ++#include <linux/platform_device.h> ++#include <linux/io.h> ++#include <linux/slab.h> ++#include <linux/i2c.h> ++#include <linux/interrupt.h> ++#include <linux/sched.h> ++#include <linux/wait.h> ++ ++/* BSC register offsets */ ++#define BSC_C 0x00 ++#define BSC_S 0x04 ++#define BSC_DLEN 0x08 ++#define BSC_A 0x0c ++#define BSC_FIFO 0x10 ++#define BSC_DIV 0x14 ++#define BSC_DEL 0x18 ++#define BSC_CLKT 0x1c ++ ++/* Bitfields in BSC_C */ ++#define BSC_C_I2CEN 0x00008000 ++#define BSC_C_INTR 0x00000400 ++#define BSC_C_INTT 0x00000200 ++#define BSC_C_INTD 0x00000100 ++#define BSC_C_ST 0x00000080 ++#define BSC_C_CLEAR_1 0x00000020 ++#define BSC_C_CLEAR_2 0x00000010 ++#define BSC_C_READ 0x00000001 ++ ++/* Bitfields in BSC_S */ ++#define BSC_S_CLKT 0x00000200 ++#define BSC_S_ERR 0x00000100 ++#define BSC_S_RXF 0x00000080 ++#define BSC_S_TXE 0x00000040 ++#define BSC_S_RXD 0x00000020 ++#define BSC_S_TXD 0x00000010 ++#define BSC_S_RXR 0x00000008 ++#define BSC_S_TXW 0x00000004 ++#define BSC_S_DONE 0x00000002 ++#define BSC_S_TA 0x00000001 ++ ++#define I2C_TIMEOUT_MS 150 ++#define I2C_WAIT_LOOP_COUNT 40 ++ ++#define DRV_NAME "bcm2708_i2c" ++ ++static unsigned int baudrate = CONFIG_I2C_BCM2708_BAUDRATE; ++module_param(baudrate, uint, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP); ++MODULE_PARM_DESC(baudrate, "The I2C baudrate"); ++ ++static bool combined = false; ++module_param(combined, bool, 0644); ++MODULE_PARM_DESC(combined, "Use combined transactions"); ++ ++struct bcm2708_i2c { ++ struct i2c_adapter adapter; ++ ++ spinlock_t lock; ++ void __iomem *base; ++ int irq; ++ struct clk *clk; ++ u32 cdiv; ++ ++ struct completion done; ++ ++ struct i2c_msg *msg; ++ int pos; ++ int nmsgs; ++ bool error; ++}; ++ ++/* ++ * This function sets the ALT mode on the I2C pins so that we can use them with ++ * the BSC hardware. ++ * ++ * FIXME: This is a hack. Use pinmux / pinctrl. ++ */ ++static void bcm2708_i2c_init_pinmode(int id) ++{ ++#define INP_GPIO(g) *(gpio+((g)/10)) &= ~(7<<(((g)%10)*3)) ++#define SET_GPIO_ALT(g,a) *(gpio+(((g)/10))) |= (((a)<=3?(a)+4:(a)==4?3:2)<<(((g)%10)*3)) ++ ++ int pin; ++ u32 *gpio = ioremap(GPIO_BASE, SZ_16K); ++ ++ BUG_ON(id != 0 && id != 1); ++ /* BSC0 is on GPIO 0 & 1, BSC1 is on GPIO 2 & 3 */ ++ for (pin = id*2+0; pin <= id*2+1; pin++) { ++ printk("bcm2708_i2c_init_pinmode(%d,%d)\n", id, pin); ++ INP_GPIO(pin); /* set mode to GPIO input first */ ++ SET_GPIO_ALT(pin, 0); /* set mode to ALT 0 */ ++ } ++ ++ iounmap(gpio); ++ ++#undef INP_GPIO ++#undef SET_GPIO_ALT ++} ++ ++static inline u32 bcm2708_rd(struct bcm2708_i2c *bi, unsigned reg) ++{ ++ return readl(bi->base + reg); ++} ++ ++static inline void bcm2708_wr(struct bcm2708_i2c *bi, unsigned reg, u32 val) ++{ ++ writel(val, bi->base + reg); ++} ++ ++static inline void bcm2708_bsc_reset(struct bcm2708_i2c *bi) ++{ ++ bcm2708_wr(bi, BSC_C, 0); ++ bcm2708_wr(bi, BSC_S, BSC_S_CLKT | BSC_S_ERR | BSC_S_DONE); ++} ++ ++static inline void bcm2708_bsc_fifo_drain(struct bcm2708_i2c *bi) ++{ ++ while ((bcm2708_rd(bi, BSC_S) & BSC_S_RXD) && (bi->pos < bi->msg->len)) ++ bi->msg->buf[bi->pos++] = bcm2708_rd(bi, BSC_FIFO); ++} ++ ++static inline void bcm2708_bsc_fifo_fill(struct bcm2708_i2c *bi) ++{ ++ while ((bcm2708_rd(bi, BSC_S) & BSC_S_TXD) && (bi->pos < bi->msg->len)) ++ bcm2708_wr(bi, BSC_FIFO, bi->msg->buf[bi->pos++]); ++} ++ ++static inline int bcm2708_bsc_setup(struct bcm2708_i2c *bi) ++{ ++ u32 cdiv, s; ++ u32 c = BSC_C_I2CEN | BSC_C_INTD | BSC_C_ST | BSC_C_CLEAR_1; ++ int wait_loops = I2C_WAIT_LOOP_COUNT; ++ ++ /* Can't call clk_get_rate as it locks a mutex and here we are spinlocked. ++ * Use the value that we cached in the probe. ++ */ ++ cdiv = bi->cdiv; ++ ++ if (bi->msg->flags & I2C_M_RD) ++ c |= BSC_C_INTR | BSC_C_READ; ++ else ++ c |= BSC_C_INTT; ++ ++ bcm2708_wr(bi, BSC_DIV, cdiv); ++ bcm2708_wr(bi, BSC_A, bi->msg->addr); ++ bcm2708_wr(bi, BSC_DLEN, bi->msg->len); ++ if (combined) ++ { ++ /* Do the next two messages meet combined transaction criteria? ++ - Current message is a write, next message is a read ++ - Both messages to same slave address ++ - Write message can fit inside FIFO (16 bytes or less) */ ++ if ( (bi->nmsgs > 1) && ++ !(bi->msg[0].flags & I2C_M_RD) && (bi->msg[1].flags & I2C_M_RD) && ++ (bi->msg[0].addr == bi->msg[1].addr) && (bi->msg[0].len <= 16)) { ++ /* Fill FIFO with entire write message (16 byte FIFO) */ ++ while (bi->pos < bi->msg->len) { ++ bcm2708_wr(bi, BSC_FIFO, bi->msg->buf[bi->pos++]); ++ } ++ /* Start write transfer (no interrupts, don't clear FIFO) */ ++ bcm2708_wr(bi, BSC_C, BSC_C_I2CEN | BSC_C_ST); ++ ++ /* poll for transfer start bit (should only take 1-20 polls) */ ++ do { ++ s = bcm2708_rd(bi, BSC_S); ++ } while (!(s & (BSC_S_TA | BSC_S_ERR | BSC_S_CLKT | BSC_S_DONE)) && --wait_loops >= 0); ++ ++ /* did we time out or some error occured? */ ++ if (wait_loops < 0 || (s & (BSC_S_ERR | BSC_S_CLKT))) { ++ return -1; ++ } ++ ++ /* Send next read message before the write transfer finishes. */ ++ bi->nmsgs--; ++ bi->msg++; ++ bi->pos = 0; ++ bcm2708_wr(bi, BSC_DLEN, bi->msg->len); ++ c = BSC_C_I2CEN | BSC_C_INTD | BSC_C_INTR | BSC_C_ST | BSC_C_READ; ++ } ++ } ++ bcm2708_wr(bi, BSC_C, c); ++ ++ return 0; ++} ++ ++static irqreturn_t bcm2708_i2c_interrupt(int irq, void *dev_id) ++{ ++ struct bcm2708_i2c *bi = dev_id; ++ bool handled = true; ++ u32 s; ++ int ret; ++ ++ spin_lock(&bi->lock); ++ ++ /* we may see camera interrupts on the "other" I2C channel ++ Just return if we've not sent anything */ ++ if (!bi->nmsgs || !bi->msg) { ++ goto early_exit; ++ } ++ ++ s = bcm2708_rd(bi, BSC_S); ++ ++ if (s & (BSC_S_CLKT | BSC_S_ERR)) { ++ bcm2708_bsc_reset(bi); ++ bi->error = true; ++ ++ bi->msg = 0; /* to inform the that all work is done */ ++ bi->nmsgs = 0; ++ /* wake up our bh */ ++ complete(&bi->done); ++ } else if (s & BSC_S_DONE) { ++ bi->nmsgs--; ++ ++ if (bi->msg->flags & I2C_M_RD) { ++ bcm2708_bsc_fifo_drain(bi); ++ } ++ ++ bcm2708_bsc_reset(bi); ++ ++ if (bi->nmsgs) { ++ /* advance to next message */ ++ bi->msg++; ++ bi->pos = 0; ++ ret = bcm2708_bsc_setup(bi); ++ if (ret < 0) { ++ bcm2708_bsc_reset(bi); ++ bi->error = true; ++ bi->msg = 0; /* to inform the that all work is done */ ++ bi->nmsgs = 0; ++ /* wake up our bh */ ++ complete(&bi->done); ++ goto early_exit; ++ } ++ } else { ++ bi->msg = 0; /* to inform the that all work is done */ ++ bi->nmsgs = 0; ++ /* wake up our bh */ ++ complete(&bi->done); ++ } ++ } else if (s & BSC_S_TXW) { ++ bcm2708_bsc_fifo_fill(bi); ++ } else if (s & BSC_S_RXR) { ++ bcm2708_bsc_fifo_drain(bi); ++ } else { ++ handled = false; ++ } ++ ++early_exit: ++ spin_unlock(&bi->lock); ++ ++ return handled ? IRQ_HANDLED : IRQ_NONE; ++} ++ ++static int bcm2708_i2c_master_xfer(struct i2c_adapter *adap, ++ struct i2c_msg *msgs, int num) ++{ ++ struct bcm2708_i2c *bi = adap->algo_data; ++ unsigned long flags; ++ int ret; ++ ++ spin_lock_irqsave(&bi->lock, flags); ++ ++ reinit_completion(&bi->done); ++ bi->msg = msgs; ++ bi->pos = 0; ++ bi->nmsgs = num; ++ bi->error = false; ++ ++ ret = bcm2708_bsc_setup(bi); ++ ++ spin_unlock_irqrestore(&bi->lock, flags); ++ ++ /* check the result of the setup */ ++ if (ret < 0) ++ { ++ dev_err(&adap->dev, "transfer setup timed out\n"); ++ goto error_timeout; ++ } ++ ++ ret = wait_for_completion_timeout(&bi->done, msecs_to_jiffies(I2C_TIMEOUT_MS)); ++ if (ret == 0) { ++ dev_err(&adap->dev, "transfer timed out\n"); ++ goto error_timeout; ++ } ++ ++ ret = bi->error ? -EIO : num; ++ return ret; ++ ++error_timeout: ++ spin_lock_irqsave(&bi->lock, flags); ++ bcm2708_bsc_reset(bi); ++ bi->msg = 0; /* to inform the interrupt handler that there's nothing else to be done */ ++ bi->nmsgs = 0; ++ spin_unlock_irqrestore(&bi->lock, flags); ++ return -ETIMEDOUT; ++} ++ ++static u32 bcm2708_i2c_functionality(struct i2c_adapter *adap) ++{ ++ return I2C_FUNC_I2C | /*I2C_FUNC_10BIT_ADDR |*/ I2C_FUNC_SMBUS_EMUL; ++} ++ ++static struct i2c_algorithm bcm2708_i2c_algorithm = { ++ .master_xfer = bcm2708_i2c_master_xfer, ++ .functionality = bcm2708_i2c_functionality, ++}; ++ ++static int bcm2708_i2c_probe(struct platform_device *pdev) ++{ ++ struct resource *regs; ++ int irq, err = -ENOMEM; ++ struct clk *clk; ++ struct bcm2708_i2c *bi; ++ struct i2c_adapter *adap; ++ unsigned long bus_hz; ++ u32 cdiv; ++ ++ 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"); ++ } ++ ++ regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); ++ if (!regs) { ++ dev_err(&pdev->dev, "could not get IO memory\n"); ++ return -ENXIO; ++ } ++ ++ irq = platform_get_irq(pdev, 0); ++ if (irq < 0) { ++ dev_err(&pdev->dev, "could not get IRQ\n"); ++ return irq; ++ } ++ ++ clk = clk_get(&pdev->dev, NULL); ++ if (IS_ERR(clk)) { ++ dev_err(&pdev->dev, "could not find clk: %ld\n", PTR_ERR(clk)); ++ return PTR_ERR(clk); ++ } ++ ++ err = clk_prepare_enable(clk); ++ if (err) { ++ dev_err(&pdev->dev, "could not enable clk: %d\n", err); ++ goto out_clk_put; ++ } ++ ++ if (!pdev->dev.of_node) ++ bcm2708_i2c_init_pinmode(pdev->id); ++ ++ bi = kzalloc(sizeof(*bi), GFP_KERNEL); ++ if (!bi) ++ goto out_clk_disable; ++ ++ platform_set_drvdata(pdev, bi); ++ ++ adap = &bi->adapter; ++ adap->class = I2C_CLASS_HWMON | I2C_CLASS_DDC; ++ adap->algo = &bcm2708_i2c_algorithm; ++ adap->algo_data = bi; ++ adap->dev.parent = &pdev->dev; ++ adap->nr = pdev->id; ++ strlcpy(adap->name, dev_name(&pdev->dev), sizeof(adap->name)); ++ adap->dev.of_node = pdev->dev.of_node; ++ ++ switch (pdev->id) { ++ case 0: ++ adap->class = I2C_CLASS_HWMON; ++ break; ++ case 1: ++ adap->class = I2C_CLASS_DDC; ++ break; ++ default: ++ dev_err(&pdev->dev, "can only bind to BSC 0 or 1\n"); ++ err = -ENXIO; ++ goto out_free_bi; ++ } ++ ++ spin_lock_init(&bi->lock); ++ init_completion(&bi->done); ++ ++ bi->base = ioremap(regs->start, resource_size(regs)); ++ if (!bi->base) { ++ dev_err(&pdev->dev, "could not remap memory\n"); ++ goto out_free_bi; ++ } ++ ++ bi->irq = irq; ++ bi->clk = clk; ++ ++ err = request_irq(irq, bcm2708_i2c_interrupt, IRQF_SHARED, ++ dev_name(&pdev->dev), bi); ++ if (err) { ++ dev_err(&pdev->dev, "could not request IRQ: %d\n", err); ++ goto out_iounmap; ++ } ++ ++ bcm2708_bsc_reset(bi); ++ ++ err = i2c_add_numbered_adapter(adap); ++ if (err < 0) { ++ dev_err(&pdev->dev, "could not add I2C adapter: %d\n", err); ++ goto out_free_irq; ++ } ++ ++ bus_hz = clk_get_rate(bi->clk); ++ cdiv = bus_hz / baudrate; ++ if (cdiv > 0xffff) { ++ cdiv = 0xffff; ++ baudrate = bus_hz / cdiv; ++ } ++ bi->cdiv = cdiv; ++ ++ dev_info(&pdev->dev, "BSC%d Controller at 0x%08lx (irq %d) (baudrate %d)\n", ++ pdev->id, (unsigned long)regs->start, irq, baudrate); ++ ++ return 0; ++ ++out_free_irq: ++ free_irq(bi->irq, bi); ++out_iounmap: ++ iounmap(bi->base); ++out_free_bi: ++ kfree(bi); ++out_clk_disable: ++ clk_disable_unprepare(clk); ++out_clk_put: ++ clk_put(clk); ++ return err; ++} ++ ++static int bcm2708_i2c_remove(struct platform_device *pdev) ++{ ++ struct bcm2708_i2c *bi = platform_get_drvdata(pdev); ++ ++ platform_set_drvdata(pdev, NULL); ++ ++ i2c_del_adapter(&bi->adapter); ++ free_irq(bi->irq, bi); ++ iounmap(bi->base); ++ clk_disable_unprepare(bi->clk); ++ clk_put(bi->clk); ++ kfree(bi); ++ ++ return 0; ++} ++ ++static const struct of_device_id bcm2708_i2c_of_match[] = { ++ { .compatible = "brcm,bcm2708-i2c" }, ++ {}, ++}; ++MODULE_DEVICE_TABLE(of, bcm2708_i2c_of_match); ++ ++static struct platform_driver bcm2708_i2c_driver = { ++ .driver = { ++ .name = DRV_NAME, ++ .owner = THIS_MODULE, ++ .of_match_table = bcm2708_i2c_of_match, ++ }, ++ .probe = bcm2708_i2c_probe, ++ .remove = bcm2708_i2c_remove, ++}; ++ ++// module_platform_driver(bcm2708_i2c_driver); ++ ++ ++static int __init bcm2708_i2c_init(void) ++{ ++ return platform_driver_register(&bcm2708_i2c_driver); ++} ++ ++static void __exit bcm2708_i2c_exit(void) ++{ ++ platform_driver_unregister(&bcm2708_i2c_driver); ++} ++ ++module_init(bcm2708_i2c_init); ++module_exit(bcm2708_i2c_exit); ++ ++ ++ ++MODULE_DESCRIPTION("BSC controller driver for Broadcom BCM2708"); ++MODULE_AUTHOR("Chris Boot <bootc@bootc.net>"); ++MODULE_LICENSE("GPL v2"); ++MODULE_ALIAS("platform:" DRV_NAME); |