From c9a9ef4170b3db3044504cd5512d0bb19c6f23c7 Mon Sep 17 00:00:00 2001 From: Mikko Perttunen Date: Fri, 5 Sep 2014 12:28:18 +0300 Subject: [PATCH 1/7] i2c: tegra: Move clk_prepare/clk_set_rate to probe Currently the i2c-tegra bus driver prepares, enables and set_rates its clocks separately for each transfer. This causes locking problems when doing I2C transfers from clock notifiers; see http://lists.infradead.org/pipermail/linux-arm-kernel/2014-July/268653.html This patch moves clk_prepare/unprepare and clk_set_rate calls to the probe function, leaving only clk_enable/disable to be done on each transfer. This solves the locking issue. Signed-off-by: Mikko Perttunen Reviewed-by: Stephen Warren Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-tegra.c | 57 +++++++++++++++++++++++++++------- 1 file changed, 45 insertions(+), 12 deletions(-) diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index 87d0371cebb7..efba1ebe16ba 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -380,34 +380,33 @@ static inline int tegra_i2c_clock_enable(struct tegra_i2c_dev *i2c_dev) { int ret; if (!i2c_dev->hw->has_single_clk_source) { - ret = clk_prepare_enable(i2c_dev->fast_clk); + ret = clk_enable(i2c_dev->fast_clk); if (ret < 0) { dev_err(i2c_dev->dev, "Enabling fast clk failed, err %d\n", ret); return ret; } } - ret = clk_prepare_enable(i2c_dev->div_clk); + ret = clk_enable(i2c_dev->div_clk); if (ret < 0) { dev_err(i2c_dev->dev, "Enabling div clk failed, err %d\n", ret); - clk_disable_unprepare(i2c_dev->fast_clk); + clk_disable(i2c_dev->fast_clk); } return ret; } static inline void tegra_i2c_clock_disable(struct tegra_i2c_dev *i2c_dev) { - clk_disable_unprepare(i2c_dev->div_clk); + clk_disable(i2c_dev->div_clk); if (!i2c_dev->hw->has_single_clk_source) - clk_disable_unprepare(i2c_dev->fast_clk); + clk_disable(i2c_dev->fast_clk); } static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev) { u32 val; int err = 0; - int clk_multiplier = I2C_CLK_MULTIPLIER_STD_FAST_MODE; u32 clk_divisor; err = tegra_i2c_clock_enable(i2c_dev); @@ -428,9 +427,6 @@ static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev) i2c_writel(i2c_dev, val, I2C_CNFG); i2c_writel(i2c_dev, 0, I2C_INT_MASK); - clk_multiplier *= (i2c_dev->hw->clk_divisor_std_fast_mode + 1); - clk_set_rate(i2c_dev->div_clk, i2c_dev->bus_clk_rate * clk_multiplier); - /* Make sure clock divisor programmed correctly */ clk_divisor = i2c_dev->hw->clk_divisor_hs_mode; clk_divisor |= i2c_dev->hw->clk_divisor_std_fast_mode << @@ -712,6 +708,7 @@ static int tegra_i2c_probe(struct platform_device *pdev) void __iomem *base; int irq; int ret = 0; + int clk_multiplier = I2C_CLK_MULTIPLIER_STD_FAST_MODE; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); base = devm_ioremap_resource(&pdev->dev, res); @@ -777,17 +774,39 @@ static int tegra_i2c_probe(struct platform_device *pdev) platform_set_drvdata(pdev, i2c_dev); + if (!i2c_dev->hw->has_single_clk_source) { + ret = clk_prepare(i2c_dev->fast_clk); + if (ret < 0) { + dev_err(i2c_dev->dev, "Clock prepare failed %d\n", ret); + return ret; + } + } + + clk_multiplier *= (i2c_dev->hw->clk_divisor_std_fast_mode + 1); + ret = clk_set_rate(i2c_dev->div_clk, + i2c_dev->bus_clk_rate * clk_multiplier); + if (ret) { + dev_err(i2c_dev->dev, "Clock rate change failed %d\n", ret); + goto unprepare_fast_clk; + } + + ret = clk_prepare(i2c_dev->div_clk); + if (ret < 0) { + dev_err(i2c_dev->dev, "Clock prepare failed %d\n", ret); + goto unprepare_fast_clk; + } + ret = tegra_i2c_init(i2c_dev); if (ret) { dev_err(&pdev->dev, "Failed to initialize i2c controller"); - return ret; + goto unprepare_div_clk; } ret = devm_request_irq(&pdev->dev, i2c_dev->irq, tegra_i2c_isr, 0, dev_name(&pdev->dev), i2c_dev); if (ret) { dev_err(&pdev->dev, "Failed to request irq %i\n", i2c_dev->irq); - return ret; + goto unprepare_div_clk; } i2c_set_adapdata(&i2c_dev->adapter, i2c_dev); @@ -803,16 +822,30 @@ static int tegra_i2c_probe(struct platform_device *pdev) ret = i2c_add_numbered_adapter(&i2c_dev->adapter); if (ret) { dev_err(&pdev->dev, "Failed to add I2C adapter\n"); - return ret; + goto unprepare_div_clk; } return 0; + +unprepare_div_clk: + clk_unprepare(i2c_dev->div_clk); + +unprepare_fast_clk: + if (!i2c_dev->hw->has_single_clk_source) + clk_unprepare(i2c_dev->fast_clk); + + return ret; } static int tegra_i2c_remove(struct platform_device *pdev) { struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev); i2c_del_adapter(&i2c_dev->adapter); + + clk_unprepare(i2c_dev->div_clk); + if (!i2c_dev->hw->has_single_clk_source) + clk_unprepare(i2c_dev->fast_clk); + return 0; } From 938916fbb8e8cb67eacb784f4eda17e2950c16c5 Mon Sep 17 00:00:00 2001 From: Sergei Shtylyov Date: Sat, 6 Sep 2014 03:34:32 +0400 Subject: [PATCH 2/7] i2c: rcar: fix RCAR_IRQ_ACK_{RECV|SEND} Bits 8-31 of all registers reflect the value of bits 0-7 on reads and should be 0 on writes, according to the manuals. RCAR_IRQ_ACK_{RECV|SEND} macros have all 1's in bits 8-31, thus going against the manuals, so fix them. Signed-off-by: Sergei Shtylyov Cc: stable@vger.kernel.org Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-rcar.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c index 1cc146cfc1f3..e506fcd3ca04 100644 --- a/drivers/i2c/busses/i2c-rcar.c +++ b/drivers/i2c/busses/i2c-rcar.c @@ -76,8 +76,8 @@ #define RCAR_IRQ_RECV (MNR | MAL | MST | MAT | MDR) #define RCAR_IRQ_STOP (MST) -#define RCAR_IRQ_ACK_SEND (~(MAT | MDE)) -#define RCAR_IRQ_ACK_RECV (~(MAT | MDR)) +#define RCAR_IRQ_ACK_SEND (~(MAT | MDE) & 0xFF) +#define RCAR_IRQ_ACK_RECV (~(MAT | MDR) & 0xFF) #define ID_LAST_MSG (1 << 0) #define ID_IOERROR (1 << 1) From 979bbf7b7ae75cfc06e09d09eda38009a3bdc4a4 Mon Sep 17 00:00:00 2001 From: Fan Du Date: Tue, 16 Sep 2014 17:21:04 +0800 Subject: [PATCH 3/7] i2c: ismt: use correct length when copy buffer In block write mode, when encapsulating dma_buffer, first element is 'command', the rest is data buffer, so only copy actual data buffer starting from block[1] with the size indicating by block[0]. Signed-off-by: Fan Du Acked-by: Neil Horman Signed-off-by: Wolfram Sang Cc: stable@kernel.org --- drivers/i2c/busses/i2c-ismt.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/i2c/busses/i2c-ismt.c b/drivers/i2c/busses/i2c-ismt.c index 984492553e95..d9ee43c80cde 100644 --- a/drivers/i2c/busses/i2c-ismt.c +++ b/drivers/i2c/busses/i2c-ismt.c @@ -497,7 +497,7 @@ static int ismt_access(struct i2c_adapter *adap, u16 addr, desc->wr_len_cmd = dma_size; desc->control |= ISMT_DESC_BLK; priv->dma_buffer[0] = command; - memcpy(&priv->dma_buffer[1], &data->block[1], dma_size); + memcpy(&priv->dma_buffer[1], &data->block[1], dma_size - 1); } else { /* Block Read */ dev_dbg(dev, "I2C_SMBUS_BLOCK_DATA: READ\n"); @@ -525,7 +525,7 @@ static int ismt_access(struct i2c_adapter *adap, u16 addr, desc->wr_len_cmd = dma_size; desc->control |= ISMT_DESC_I2C; priv->dma_buffer[0] = command; - memcpy(&priv->dma_buffer[1], &data->block[1], dma_size); + memcpy(&priv->dma_buffer[1], &data->block[1], dma_size - 1); } else { /* i2c Block Read */ dev_dbg(dev, "I2C_SMBUS_I2C_BLOCK_DATA: READ\n"); From a4780d039ca5c3ef318db084f1bfc6ebed6876c8 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Janusz=20U=C5=BCycki?= Date: Tue, 9 Sep 2014 18:19:30 +0200 Subject: [PATCH 4/7] i2c: mxs: fix error message in pio transfer If I2C_M_RD flag is set SELECT command is sent and afterward READ command. The patch fixes READ command to return READ failure error message instead of SELECT failure error message. Signed-off-by: Janusz Uzycki Acked-by: Marek Vasut Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-mxs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.c index 7170fc892829..65a21fed08b5 100644 --- a/drivers/i2c/busses/i2c-mxs.c +++ b/drivers/i2c/busses/i2c-mxs.c @@ -429,7 +429,7 @@ static int mxs_i2c_pio_setup_xfer(struct i2c_adapter *adap, ret = mxs_i2c_pio_wait_xfer_end(i2c); if (ret) { dev_err(i2c->dev, - "PIO: Failed to send SELECT command!\n"); + "PIO: Failed to send READ command!\n"); goto cleanup; } From b4a7bd7a386dc6b0bb49cb47614e06e8295d495a Mon Sep 17 00:00:00 2001 From: addy ke Date: Mon, 8 Sep 2014 11:38:25 +0800 Subject: [PATCH 5/7] i2c: rk3x: fix divisor calculation for SCL frequency I2C_CLKDIV register descripted in the previous version of RK3x chip manual is incorrect. Plus 1 is required. The correct formula: - T(SCL_HIGH) = T(PCLK) * (CLKDIVH + 1) * 8 - T(SCL_LOW) = T(PCLK) * (CLKDIVL + 1) * 8 - (SCL Divsor) = 8 * ((CLKDIVL + 1) + (CLKDIVH + 1)) - SCL = PCLK / (CLK Divsor) It will be updated to the latest version of chip manual. Signed-off-by: Addy Ke Reviewed-by: Doug Anderson Signed-off-by: Wolfram Sang Cc: stable@kernel.org --- drivers/i2c/busses/i2c-rk3x.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-rk3x.c index e637c32ae517..93cfc837200b 100644 --- a/drivers/i2c/busses/i2c-rk3x.c +++ b/drivers/i2c/busses/i2c-rk3x.c @@ -433,12 +433,11 @@ static void rk3x_i2c_set_scl_rate(struct rk3x_i2c *i2c, unsigned long scl_rate) unsigned long i2c_rate = clk_get_rate(i2c->clk); unsigned int div; - /* SCL rate = (clk rate) / (8 * DIV) */ - div = DIV_ROUND_UP(i2c_rate, scl_rate * 8); - - /* The lower and upper half of the CLKDIV reg describe the length of - * SCL low & high periods. */ - div = DIV_ROUND_UP(div, 2); + /* set DIV = DIVH = DIVL + * SCL rate = (clk rate) / (8 * (DIVH + 1 + DIVL + 1)) + * = (clk rate) / (16 * (DIV + 1)) + */ + div = DIV_ROUND_UP(i2c_rate, scl_rate * 16) - 1; i2c_writel(i2c, (div << 16) | (div & 0xffff), REG_CLKDIV); } From 17f4a5c47f28de9ea59182f48d07f8c44ee5dcc9 Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Mon, 22 Sep 2014 19:41:00 +0200 Subject: [PATCH 6/7] i2c: move acpi code back into the core Commit 5d98e61d337c ("I2C/ACPI: Add i2c ACPI operation region support") renamed the i2c-core module. This may cause regressions for distributions, so put the ACPI code back into the core. Reported-by: Jean Delvare Signed-off-by: Wolfram Sang Tested-by: Lan Tianyu Tested-by: Mika Westerberg --- MAINTAINERS | 1 - drivers/i2c/Makefile | 5 +- drivers/i2c/i2c-acpi.c | 364 ----------------------------------------- drivers/i2c/i2c-core.c | 354 +++++++++++++++++++++++++++++++++++++++ include/linux/i2c.h | 16 -- 5 files changed, 355 insertions(+), 385 deletions(-) delete mode 100644 drivers/i2c/i2c-acpi.c diff --git a/MAINTAINERS b/MAINTAINERS index 809ecd680d88..e3682d0dea1e 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -4477,7 +4477,6 @@ M: Mika Westerberg L: linux-i2c@vger.kernel.org L: linux-acpi@vger.kernel.org S: Maintained -F: drivers/i2c/i2c-acpi.c I2C-TAOS-EVM DRIVER M: Jean Delvare diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile index e0228b228256..1722f50f2473 100644 --- a/drivers/i2c/Makefile +++ b/drivers/i2c/Makefile @@ -2,11 +2,8 @@ # Makefile for the i2c core. # -i2ccore-y := i2c-core.o -i2ccore-$(CONFIG_ACPI) += i2c-acpi.o - obj-$(CONFIG_I2C_BOARDINFO) += i2c-boardinfo.o -obj-$(CONFIG_I2C) += i2ccore.o +obj-$(CONFIG_I2C) += i2c-core.o obj-$(CONFIG_I2C_SMBUS) += i2c-smbus.o obj-$(CONFIG_I2C_CHARDEV) += i2c-dev.o obj-$(CONFIG_I2C_MUX) += i2c-mux.o diff --git a/drivers/i2c/i2c-acpi.c b/drivers/i2c/i2c-acpi.c deleted file mode 100644 index 0dbc18c15c43..000000000000 --- a/drivers/i2c/i2c-acpi.c +++ /dev/null @@ -1,364 +0,0 @@ -/* - * I2C ACPI code - * - * Copyright (C) 2014 Intel Corp - * - * Author: Lan Tianyu - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * - * 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. - */ -#define pr_fmt(fmt) "I2C/ACPI : " fmt - -#include -#include -#include -#include -#include - -struct acpi_i2c_handler_data { - struct acpi_connection_info info; - struct i2c_adapter *adapter; -}; - -struct gsb_buffer { - u8 status; - u8 len; - union { - u16 wdata; - u8 bdata; - u8 data[0]; - }; -} __packed; - -static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data) -{ - struct i2c_board_info *info = data; - - if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) { - struct acpi_resource_i2c_serialbus *sb; - - sb = &ares->data.i2c_serial_bus; - if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) { - info->addr = sb->slave_address; - if (sb->access_mode == ACPI_I2C_10BIT_MODE) - info->flags |= I2C_CLIENT_TEN; - } - } else if (info->irq < 0) { - struct resource r; - - if (acpi_dev_resource_interrupt(ares, 0, &r)) - info->irq = r.start; - } - - /* Tell the ACPI core to skip this resource */ - return 1; -} - -static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level, - void *data, void **return_value) -{ - struct i2c_adapter *adapter = data; - struct list_head resource_list; - struct i2c_board_info info; - struct acpi_device *adev; - int ret; - - if (acpi_bus_get_device(handle, &adev)) - return AE_OK; - if (acpi_bus_get_status(adev) || !adev->status.present) - return AE_OK; - - memset(&info, 0, sizeof(info)); - info.acpi_node.companion = adev; - info.irq = -1; - - INIT_LIST_HEAD(&resource_list); - ret = acpi_dev_get_resources(adev, &resource_list, - acpi_i2c_add_resource, &info); - acpi_dev_free_resource_list(&resource_list); - - if (ret < 0 || !info.addr) - return AE_OK; - - adev->power.flags.ignore_parent = true; - strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type)); - if (!i2c_new_device(adapter, &info)) { - adev->power.flags.ignore_parent = false; - dev_err(&adapter->dev, - "failed to add I2C device %s from ACPI\n", - dev_name(&adev->dev)); - } - - return AE_OK; -} - -/** - * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter - * @adap: pointer to adapter - * - * Enumerate all I2C slave devices behind this adapter by walking the ACPI - * namespace. When a device is found it will be added to the Linux device - * model and bound to the corresponding ACPI handle. - */ -void acpi_i2c_register_devices(struct i2c_adapter *adap) -{ - acpi_handle handle; - acpi_status status; - - if (!adap->dev.parent) - return; - - handle = ACPI_HANDLE(adap->dev.parent); - if (!handle) - return; - - status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, - acpi_i2c_add_device, NULL, - adap, NULL); - if (ACPI_FAILURE(status)) - dev_warn(&adap->dev, "failed to enumerate I2C slaves\n"); -} - -#ifdef CONFIG_ACPI_I2C_OPREGION -static int acpi_gsb_i2c_read_bytes(struct i2c_client *client, - u8 cmd, u8 *data, u8 data_len) -{ - - struct i2c_msg msgs[2]; - int ret; - u8 *buffer; - - buffer = kzalloc(data_len, GFP_KERNEL); - if (!buffer) - return AE_NO_MEMORY; - - msgs[0].addr = client->addr; - msgs[0].flags = client->flags; - msgs[0].len = 1; - msgs[0].buf = &cmd; - - msgs[1].addr = client->addr; - msgs[1].flags = client->flags | I2C_M_RD; - msgs[1].len = data_len; - msgs[1].buf = buffer; - - ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); - if (ret < 0) - dev_err(&client->adapter->dev, "i2c read failed\n"); - else - memcpy(data, buffer, data_len); - - kfree(buffer); - return ret; -} - -static int acpi_gsb_i2c_write_bytes(struct i2c_client *client, - u8 cmd, u8 *data, u8 data_len) -{ - - struct i2c_msg msgs[1]; - u8 *buffer; - int ret = AE_OK; - - buffer = kzalloc(data_len + 1, GFP_KERNEL); - if (!buffer) - return AE_NO_MEMORY; - - buffer[0] = cmd; - memcpy(buffer + 1, data, data_len); - - msgs[0].addr = client->addr; - msgs[0].flags = client->flags; - msgs[0].len = data_len + 1; - msgs[0].buf = buffer; - - ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); - if (ret < 0) - dev_err(&client->adapter->dev, "i2c write failed\n"); - - kfree(buffer); - return ret; -} - -static acpi_status -acpi_i2c_space_handler(u32 function, acpi_physical_address command, - u32 bits, u64 *value64, - void *handler_context, void *region_context) -{ - struct gsb_buffer *gsb = (struct gsb_buffer *)value64; - struct acpi_i2c_handler_data *data = handler_context; - struct acpi_connection_info *info = &data->info; - struct acpi_resource_i2c_serialbus *sb; - struct i2c_adapter *adapter = data->adapter; - struct i2c_client client; - struct acpi_resource *ares; - u32 accessor_type = function >> 16; - u8 action = function & ACPI_IO_MASK; - acpi_status ret = AE_OK; - int status; - - ret = acpi_buffer_to_resource(info->connection, info->length, &ares); - if (ACPI_FAILURE(ret)) - return ret; - - if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) { - ret = AE_BAD_PARAMETER; - goto err; - } - - sb = &ares->data.i2c_serial_bus; - if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) { - ret = AE_BAD_PARAMETER; - goto err; - } - - memset(&client, 0, sizeof(client)); - client.adapter = adapter; - client.addr = sb->slave_address; - client.flags = 0; - - if (sb->access_mode == ACPI_I2C_10BIT_MODE) - client.flags |= I2C_CLIENT_TEN; - - switch (accessor_type) { - case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV: - if (action == ACPI_READ) { - status = i2c_smbus_read_byte(&client); - if (status >= 0) { - gsb->bdata = status; - status = 0; - } - } else { - status = i2c_smbus_write_byte(&client, gsb->bdata); - } - break; - - case ACPI_GSB_ACCESS_ATTRIB_BYTE: - if (action == ACPI_READ) { - status = i2c_smbus_read_byte_data(&client, command); - if (status >= 0) { - gsb->bdata = status; - status = 0; - } - } else { - status = i2c_smbus_write_byte_data(&client, command, - gsb->bdata); - } - break; - - case ACPI_GSB_ACCESS_ATTRIB_WORD: - if (action == ACPI_READ) { - status = i2c_smbus_read_word_data(&client, command); - if (status >= 0) { - gsb->wdata = status; - status = 0; - } - } else { - status = i2c_smbus_write_word_data(&client, command, - gsb->wdata); - } - break; - - case ACPI_GSB_ACCESS_ATTRIB_BLOCK: - if (action == ACPI_READ) { - status = i2c_smbus_read_block_data(&client, command, - gsb->data); - if (status >= 0) { - gsb->len = status; - status = 0; - } - } else { - status = i2c_smbus_write_block_data(&client, command, - gsb->len, gsb->data); - } - break; - - case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE: - if (action == ACPI_READ) { - status = acpi_gsb_i2c_read_bytes(&client, command, - gsb->data, info->access_length); - if (status > 0) - status = 0; - } else { - status = acpi_gsb_i2c_write_bytes(&client, command, - gsb->data, info->access_length); - } - break; - - default: - pr_info("protocol(0x%02x) is not supported.\n", accessor_type); - ret = AE_BAD_PARAMETER; - goto err; - } - - gsb->status = status; - - err: - ACPI_FREE(ares); - return ret; -} - - -int acpi_i2c_install_space_handler(struct i2c_adapter *adapter) -{ - acpi_handle handle = ACPI_HANDLE(adapter->dev.parent); - struct acpi_i2c_handler_data *data; - acpi_status status; - - if (!handle) - return -ENODEV; - - data = kzalloc(sizeof(struct acpi_i2c_handler_data), - GFP_KERNEL); - if (!data) - return -ENOMEM; - - data->adapter = adapter; - status = acpi_bus_attach_private_data(handle, (void *)data); - if (ACPI_FAILURE(status)) { - kfree(data); - return -ENOMEM; - } - - status = acpi_install_address_space_handler(handle, - ACPI_ADR_SPACE_GSBUS, - &acpi_i2c_space_handler, - NULL, - data); - if (ACPI_FAILURE(status)) { - dev_err(&adapter->dev, "Error installing i2c space handler\n"); - acpi_bus_detach_private_data(handle); - kfree(data); - return -ENOMEM; - } - - return 0; -} - -void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter) -{ - acpi_handle handle = ACPI_HANDLE(adapter->dev.parent); - struct acpi_i2c_handler_data *data; - acpi_status status; - - if (!handle) - return; - - acpi_remove_address_space_handler(handle, - ACPI_ADR_SPACE_GSBUS, - &acpi_i2c_space_handler); - - status = acpi_bus_get_private_data(handle, (void **)&data); - if (ACPI_SUCCESS(status)) - kfree(data); - - acpi_bus_detach_private_data(handle); -} -#endif diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 632057a44615..b696ac7e6d86 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -27,6 +27,8 @@ OF support is copyright (c) 2008 Jochen Friedrich (based on a previous patch from Jon Smirl ) and (c) 2013 Wolfram Sang + I2C ACPI code Copyright (C) 2014 Intel Corp + Author: Lan Tianyu */ #include @@ -78,6 +80,358 @@ void i2c_transfer_trace_unreg(void) static_key_slow_dec(&i2c_trace_msg); } +#if defined(CONFIG_ACPI) +struct acpi_i2c_handler_data { + struct acpi_connection_info info; + struct i2c_adapter *adapter; +}; + +struct gsb_buffer { + u8 status; + u8 len; + union { + u16 wdata; + u8 bdata; + u8 data[0]; + }; +} __packed; + +static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data) +{ + struct i2c_board_info *info = data; + + if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) { + struct acpi_resource_i2c_serialbus *sb; + + sb = &ares->data.i2c_serial_bus; + if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) { + info->addr = sb->slave_address; + if (sb->access_mode == ACPI_I2C_10BIT_MODE) + info->flags |= I2C_CLIENT_TEN; + } + } else if (info->irq < 0) { + struct resource r; + + if (acpi_dev_resource_interrupt(ares, 0, &r)) + info->irq = r.start; + } + + /* Tell the ACPI core to skip this resource */ + return 1; +} + +static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level, + void *data, void **return_value) +{ + struct i2c_adapter *adapter = data; + struct list_head resource_list; + struct i2c_board_info info; + struct acpi_device *adev; + int ret; + + if (acpi_bus_get_device(handle, &adev)) + return AE_OK; + if (acpi_bus_get_status(adev) || !adev->status.present) + return AE_OK; + + memset(&info, 0, sizeof(info)); + info.acpi_node.companion = adev; + info.irq = -1; + + INIT_LIST_HEAD(&resource_list); + ret = acpi_dev_get_resources(adev, &resource_list, + acpi_i2c_add_resource, &info); + acpi_dev_free_resource_list(&resource_list); + + if (ret < 0 || !info.addr) + return AE_OK; + + adev->power.flags.ignore_parent = true; + strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type)); + if (!i2c_new_device(adapter, &info)) { + adev->power.flags.ignore_parent = false; + dev_err(&adapter->dev, + "failed to add I2C device %s from ACPI\n", + dev_name(&adev->dev)); + } + + return AE_OK; +} + +/** + * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter + * @adap: pointer to adapter + * + * Enumerate all I2C slave devices behind this adapter by walking the ACPI + * namespace. When a device is found it will be added to the Linux device + * model and bound to the corresponding ACPI handle. + */ +static void acpi_i2c_register_devices(struct i2c_adapter *adap) +{ + acpi_handle handle; + acpi_status status; + + if (!adap->dev.parent) + return; + + handle = ACPI_HANDLE(adap->dev.parent); + if (!handle) + return; + + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, + acpi_i2c_add_device, NULL, + adap, NULL); + if (ACPI_FAILURE(status)) + dev_warn(&adap->dev, "failed to enumerate I2C slaves\n"); +} + +#else /* CONFIG_ACPI */ +static inline void acpi_i2c_register_devices(struct i2c_adapter *adap) { } +#endif /* CONFIG_ACPI */ + +#ifdef CONFIG_ACPI_I2C_OPREGION +static int acpi_gsb_i2c_read_bytes(struct i2c_client *client, + u8 cmd, u8 *data, u8 data_len) +{ + + struct i2c_msg msgs[2]; + int ret; + u8 *buffer; + + buffer = kzalloc(data_len, GFP_KERNEL); + if (!buffer) + return AE_NO_MEMORY; + + msgs[0].addr = client->addr; + msgs[0].flags = client->flags; + msgs[0].len = 1; + msgs[0].buf = &cmd; + + msgs[1].addr = client->addr; + msgs[1].flags = client->flags | I2C_M_RD; + msgs[1].len = data_len; + msgs[1].buf = buffer; + + ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); + if (ret < 0) + dev_err(&client->adapter->dev, "i2c read failed\n"); + else + memcpy(data, buffer, data_len); + + kfree(buffer); + return ret; +} + +static int acpi_gsb_i2c_write_bytes(struct i2c_client *client, + u8 cmd, u8 *data, u8 data_len) +{ + + struct i2c_msg msgs[1]; + u8 *buffer; + int ret = AE_OK; + + buffer = kzalloc(data_len + 1, GFP_KERNEL); + if (!buffer) + return AE_NO_MEMORY; + + buffer[0] = cmd; + memcpy(buffer + 1, data, data_len); + + msgs[0].addr = client->addr; + msgs[0].flags = client->flags; + msgs[0].len = data_len + 1; + msgs[0].buf = buffer; + + ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); + if (ret < 0) + dev_err(&client->adapter->dev, "i2c write failed\n"); + + kfree(buffer); + return ret; +} + +static acpi_status +acpi_i2c_space_handler(u32 function, acpi_physical_address command, + u32 bits, u64 *value64, + void *handler_context, void *region_context) +{ + struct gsb_buffer *gsb = (struct gsb_buffer *)value64; + struct acpi_i2c_handler_data *data = handler_context; + struct acpi_connection_info *info = &data->info; + struct acpi_resource_i2c_serialbus *sb; + struct i2c_adapter *adapter = data->adapter; + struct i2c_client client; + struct acpi_resource *ares; + u32 accessor_type = function >> 16; + u8 action = function & ACPI_IO_MASK; + acpi_status ret = AE_OK; + int status; + + ret = acpi_buffer_to_resource(info->connection, info->length, &ares); + if (ACPI_FAILURE(ret)) + return ret; + + if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) { + ret = AE_BAD_PARAMETER; + goto err; + } + + sb = &ares->data.i2c_serial_bus; + if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) { + ret = AE_BAD_PARAMETER; + goto err; + } + + memset(&client, 0, sizeof(client)); + client.adapter = adapter; + client.addr = sb->slave_address; + client.flags = 0; + + if (sb->access_mode == ACPI_I2C_10BIT_MODE) + client.flags |= I2C_CLIENT_TEN; + + switch (accessor_type) { + case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV: + if (action == ACPI_READ) { + status = i2c_smbus_read_byte(&client); + if (status >= 0) { + gsb->bdata = status; + status = 0; + } + } else { + status = i2c_smbus_write_byte(&client, gsb->bdata); + } + break; + + case ACPI_GSB_ACCESS_ATTRIB_BYTE: + if (action == ACPI_READ) { + status = i2c_smbus_read_byte_data(&client, command); + if (status >= 0) { + gsb->bdata = status; + status = 0; + } + } else { + status = i2c_smbus_write_byte_data(&client, command, + gsb->bdata); + } + break; + + case ACPI_GSB_ACCESS_ATTRIB_WORD: + if (action == ACPI_READ) { + status = i2c_smbus_read_word_data(&client, command); + if (status >= 0) { + gsb->wdata = status; + status = 0; + } + } else { + status = i2c_smbus_write_word_data(&client, command, + gsb->wdata); + } + break; + + case ACPI_GSB_ACCESS_ATTRIB_BLOCK: + if (action == ACPI_READ) { + status = i2c_smbus_read_block_data(&client, command, + gsb->data); + if (status >= 0) { + gsb->len = status; + status = 0; + } + } else { + status = i2c_smbus_write_block_data(&client, command, + gsb->len, gsb->data); + } + break; + + case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE: + if (action == ACPI_READ) { + status = acpi_gsb_i2c_read_bytes(&client, command, + gsb->data, info->access_length); + if (status > 0) + status = 0; + } else { + status = acpi_gsb_i2c_write_bytes(&client, command, + gsb->data, info->access_length); + } + break; + + default: + pr_info("protocol(0x%02x) is not supported.\n", accessor_type); + ret = AE_BAD_PARAMETER; + goto err; + } + + gsb->status = status; + + err: + ACPI_FREE(ares); + return ret; +} + + +static int acpi_i2c_install_space_handler(struct i2c_adapter *adapter) +{ + acpi_handle handle = ACPI_HANDLE(adapter->dev.parent); + struct acpi_i2c_handler_data *data; + acpi_status status; + + if (!handle) + return -ENODEV; + + data = kzalloc(sizeof(struct acpi_i2c_handler_data), + GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->adapter = adapter; + status = acpi_bus_attach_private_data(handle, (void *)data); + if (ACPI_FAILURE(status)) { + kfree(data); + return -ENOMEM; + } + + status = acpi_install_address_space_handler(handle, + ACPI_ADR_SPACE_GSBUS, + &acpi_i2c_space_handler, + NULL, + data); + if (ACPI_FAILURE(status)) { + dev_err(&adapter->dev, "Error installing i2c space handler\n"); + acpi_bus_detach_private_data(handle); + kfree(data); + return -ENOMEM; + } + + return 0; +} + +static void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter) +{ + acpi_handle handle = ACPI_HANDLE(adapter->dev.parent); + struct acpi_i2c_handler_data *data; + acpi_status status; + + if (!handle) + return; + + acpi_remove_address_space_handler(handle, + ACPI_ADR_SPACE_GSBUS, + &acpi_i2c_space_handler); + + status = acpi_bus_get_private_data(handle, (void **)&data); + if (ACPI_SUCCESS(status)) + kfree(data); + + acpi_bus_detach_private_data(handle); +} +#else /* CONFIG_ACPI_I2C_OPREGION */ +static inline void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter) +{ } + +static inline int acpi_i2c_install_space_handler(struct i2c_adapter *adapter) +{ return 0; } +#endif /* CONFIG_ACPI_I2C_OPREGION */ + /* ------------------------------------------------------------------------- */ static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, diff --git a/include/linux/i2c.h b/include/linux/i2c.h index a95efeb53a8b..b556e0ab946f 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -577,20 +577,4 @@ static inline struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node } #endif /* CONFIG_OF */ -#ifdef CONFIG_ACPI -void acpi_i2c_register_devices(struct i2c_adapter *adap); -#else -static inline void acpi_i2c_register_devices(struct i2c_adapter *adap) { } -#endif /* CONFIG_ACPI */ - -#ifdef CONFIG_ACPI_I2C_OPREGION -int acpi_i2c_install_space_handler(struct i2c_adapter *adapter); -void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter); -#else -static inline void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter) -{ } -static inline int acpi_i2c_install_space_handler(struct i2c_adapter *adapter) -{ return 0; } -#endif /* CONFIG_ACPI_I2C_OPREGION */ - #endif /* _LINUX_I2C_H */ From 0aef44e84ad16cd87a88df78773fd81ecca34f11 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Peter=20H=C3=BCwe?= Date: Fri, 12 Sep 2014 21:09:47 +0200 Subject: [PATCH 7/7] i2c: acpi: Fix NULL Pointer dereference If adapter->dev.parent == NULL there is a NULL pointer dereference in acpi_i2c_install_space_handler and acpi_i2c_remove_space_handler. This is present since introduction of this code: 366047515c6e "i2c: rework kernel config I2C_ACPI" or even da3c6647ee08 "I2C/ACPI: Clean up I2C ACPI code and Add CONFIG_I2C_ACPI" The adapter->dev.parent == NULL case is valid for the i2c_stub, so loading i2c_stub with ACPI_I2C_OPREGION enabled results in an oops. This is also valid at least for i2c_tiny_usb and i2c_robotfuzz_osif. Fix by checking whether it is null before calling ACPI_HANDLE. Signed-off-by: Peter Huewe Acked-by: Mika Westerberg Signed-off-by: Wolfram Sang --- drivers/i2c/i2c-core.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index b696ac7e6d86..ccfbbab82a15 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -371,10 +371,15 @@ acpi_i2c_space_handler(u32 function, acpi_physical_address command, static int acpi_i2c_install_space_handler(struct i2c_adapter *adapter) { - acpi_handle handle = ACPI_HANDLE(adapter->dev.parent); + acpi_handle handle; struct acpi_i2c_handler_data *data; acpi_status status; + if (!adapter->dev.parent) + return -ENODEV; + + handle = ACPI_HANDLE(adapter->dev.parent); + if (!handle) return -ENODEV; @@ -407,10 +412,15 @@ static int acpi_i2c_install_space_handler(struct i2c_adapter *adapter) static void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter) { - acpi_handle handle = ACPI_HANDLE(adapter->dev.parent); + acpi_handle handle; struct acpi_i2c_handler_data *data; acpi_status status; + if (!adapter->dev.parent) + return; + + handle = ACPI_HANDLE(adapter->dev.parent); + if (!handle) return;