From 371a015344b6e270e7e3632107d9554ec6d27a6b Mon Sep 17 00:00:00 2001 From: "Yadi.hu" Date: Sun, 18 Sep 2016 18:52:31 +0800 Subject: [PATCH 1/3] i2c-eg20t: fix race between i2c init and interrupt enable the eg20t driver call request_irq() function before the pch_base_address, base address of i2c controller's register, is assigned an effective value. there is one possible scenario that an interrupt which isn't inside eg20t arrives immediately after request_irq() is executed when i2c controller shares an interrupt number with others. since the interrupt handler pch_i2c_handler() has already active as shared action, it will be called and read its own register to determine if this interrupt is from itself. At that moment, since base address of i2c registers is not remapped in kernel space yet,so the INT handler will access an illegal address and then a error occurs. Signed-off-by: Yadi.hu Signed-off-by: Wolfram Sang Cc: stable@kernel.org --- drivers/i2c/busses/i2c-eg20t.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/drivers/i2c/busses/i2c-eg20t.c b/drivers/i2c/busses/i2c-eg20t.c index 137125b5eae7..5ce71ce7b6c4 100644 --- a/drivers/i2c/busses/i2c-eg20t.c +++ b/drivers/i2c/busses/i2c-eg20t.c @@ -773,13 +773,6 @@ static int pch_i2c_probe(struct pci_dev *pdev, /* Set the number of I2C channel instance */ adap_info->ch_num = id->driver_data; - ret = request_irq(pdev->irq, pch_i2c_handler, IRQF_SHARED, - KBUILD_MODNAME, adap_info); - if (ret) { - pch_pci_err(pdev, "request_irq FAILED\n"); - goto err_request_irq; - } - for (i = 0; i < adap_info->ch_num; i++) { pch_adap = &adap_info->pch_data[i].pch_adapter; adap_info->pch_i2c_suspended = false; @@ -797,6 +790,17 @@ static int pch_i2c_probe(struct pci_dev *pdev, pch_adap->dev.of_node = pdev->dev.of_node; pch_adap->dev.parent = &pdev->dev; + } + + ret = request_irq(pdev->irq, pch_i2c_handler, IRQF_SHARED, + KBUILD_MODNAME, adap_info); + if (ret) { + pch_pci_err(pdev, "request_irq FAILED\n"); + goto err_request_irq; + } + + for (i = 0; i < adap_info->ch_num; i++) { + pch_adap = &adap_info->pch_data[i].pch_adapter; pch_i2c_init(&adap_info->pch_data[i]); From 463e8f845cbf1c01e4cc8aeef1703212991d8e1e Mon Sep 17 00:00:00 2001 From: Peter Rosin Date: Wed, 14 Sep 2016 15:24:12 +0200 Subject: [PATCH 2/3] i2c: mux: pca954x: retry updating the mux selection on failure The cached value of the last selected channel prevents retries on the next call, even on failure to update the selected channel. Fix that. Signed-off-by: Peter Rosin Signed-off-by: Wolfram Sang Cc: stable@kernel.org --- drivers/i2c/muxes/i2c-mux-pca954x.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c index 528e755c468f..3278ebf1cc5c 100644 --- a/drivers/i2c/muxes/i2c-mux-pca954x.c +++ b/drivers/i2c/muxes/i2c-mux-pca954x.c @@ -164,7 +164,7 @@ static int pca954x_select_chan(struct i2c_mux_core *muxc, u32 chan) /* Only select the channel if its different from the last channel */ if (data->last_chan != regval) { ret = pca954x_reg_write(muxc->parent, client, regval); - data->last_chan = regval; + data->last_chan = ret ? 0 : regval; } return ret; From 331dcf421c34d227784d07943eb01e4023a42b0a Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Thu, 25 Aug 2016 12:23:39 +0100 Subject: [PATCH 3/3] i2c: qup: skip qup_i2c_suspend if the device is already runtime suspended If the i2c device is already runtime suspended, if qup_i2c_suspend is executed during suspend-to-idle or suspend-to-ram it will result in the following splat: WARNING: CPU: 3 PID: 1593 at drivers/clk/clk.c:476 clk_core_unprepare+0x80/0x90 Modules linked in: CPU: 3 PID: 1593 Comm: bash Tainted: G W 4.8.0-rc3 #14 Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT) PC is at clk_core_unprepare+0x80/0x90 LR is at clk_unprepare+0x28/0x40 pc : [] lr : [] pstate: 60000145 Call trace: clk_core_unprepare+0x80/0x90 qup_i2c_disable_clocks+0x2c/0x68 qup_i2c_suspend+0x10/0x20 platform_pm_suspend+0x24/0x68 ... This patch fixes the issue by executing qup_i2c_pm_suspend_runtime conditionally in qup_i2c_suspend. Signed-off-by: Sudeep Holla Reviewed-by: Andy Gross Signed-off-by: Wolfram Sang Cc: stable@kernel.org --- drivers/i2c/busses/i2c-qup.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c index 501bd15cb78e..a8497cfdae6f 100644 --- a/drivers/i2c/busses/i2c-qup.c +++ b/drivers/i2c/busses/i2c-qup.c @@ -1599,7 +1599,8 @@ static int qup_i2c_pm_resume_runtime(struct device *device) #ifdef CONFIG_PM_SLEEP static int qup_i2c_suspend(struct device *device) { - qup_i2c_pm_suspend_runtime(device); + if (!pm_runtime_suspended(device)) + return qup_i2c_pm_suspend_runtime(device); return 0; }