Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754855AbcCRIst (ORCPT ); Fri, 18 Mar 2016 04:48:49 -0400 Received: from mail-wm0-f66.google.com ([74.125.82.66]:33426 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750937AbcCRIq6 (ORCPT ); Fri, 18 Mar 2016 04:46:58 -0400 From: Jan Glauber To: Wolfram Sang Cc: linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org, David Daney , David Daney , Jan Glauber Subject: [PATCH v4 07/14] i2c-octeon: Add support for cn78xx chips Date: Fri, 18 Mar 2016 09:46:32 +0100 Message-Id: X-Mailer: git-send-email 1.9.1 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6190 Lines: 223 From: David Daney cn78xx has a different interrupt architecture, so we have to manage the interrupts differently. Signed-off-by: David Daney Signed-off-by: Jan Glauber --- drivers/i2c/busses/i2c-octeon.c | 131 ++++++++++++++++++++++++++++++++++++---- 1 file changed, 120 insertions(+), 11 deletions(-) diff --git a/drivers/i2c/busses/i2c-octeon.c b/drivers/i2c/busses/i2c-octeon.c index 0e3611a..f409f8f 100644 --- a/drivers/i2c/busses/i2c-octeon.c +++ b/drivers/i2c/busses/i2c-octeon.c @@ -11,6 +11,7 @@ * warranty of any kind, whether express or implied. */ +#include #include #include #include @@ -112,11 +113,18 @@ struct octeon_i2c { wait_queue_head_t queue; struct i2c_adapter adap; int irq; + int hlc_irq; /* For cn7890 only */ u32 twsi_freq; int sys_freq; void __iomem *twsi_base; struct device *dev; bool hlc_enabled; + void (*int_en)(struct octeon_i2c *); + void (*int_dis)(struct octeon_i2c *); + void (*hlc_int_en)(struct octeon_i2c *); + void (*hlc_int_dis)(struct octeon_i2c *); + atomic_t int_en_cnt; + atomic_t hlc_int_en_cnt; }; static int reset_how; @@ -214,6 +222,58 @@ static void octeon_i2c_disable_hlc(struct octeon_i2c *i2c) } /** + * octeon_i2c_int_enable78 - enable the CORE interrupt + * @i2c: The struct octeon_i2c + * + * The interrupt will be asserted when there is non-STAT_IDLE state in the + * SW_TWSI_EOP_TWSI_STAT register. + */ +static void octeon_i2c_int_enable78(struct octeon_i2c *i2c) +{ + atomic_inc_return(&i2c->int_en_cnt); + enable_irq(i2c->irq); +} + +static void __octeon_i2c_irq_disable(atomic_t *cnt, int irq) +{ + int count; + + /* + * The interrupt can be disabled in two places, but we only + * want to make the disable_irq_nosync() call once, so keep + * track with the atomic variable. + */ + count = atomic_dec_if_positive(cnt); + if (count >= 0) + disable_irq_nosync(irq); +} + +/* disable the CORE interrupt */ +static void octeon_i2c_int_disable78(struct octeon_i2c *i2c) +{ + __octeon_i2c_irq_disable(&i2c->int_en_cnt, i2c->irq); +} + +/** + * octeon_i2c_hlc_int_enable78 - enable the ST interrupt + * @i2c: The struct octeon_i2c + * + * The interrupt will be asserted when there is non-STAT_IDLE state in + * the SW_TWSI_EOP_TWSI_STAT register. + */ +static void octeon_i2c_hlc_int_enable78(struct octeon_i2c *i2c) +{ + atomic_inc_return(&i2c->hlc_int_en_cnt); + enable_irq(i2c->hlc_irq); +} + +/* disable the ST interrupt */ +static void octeon_i2c_hlc_int_disable78(struct octeon_i2c *i2c) +{ + __octeon_i2c_irq_disable(&i2c->hlc_int_en_cnt, i2c->hlc_irq); +} + +/** * octeon_i2c_unblock - unblock the bus * @i2c: The struct octeon_i2c * @@ -250,7 +310,18 @@ static irqreturn_t octeon_i2c_isr(int irq, void *dev_id) { struct octeon_i2c *i2c = dev_id; - octeon_i2c_int_disable(i2c); + i2c->int_dis(i2c); + wake_up(&i2c->queue); + + return IRQ_HANDLED; +} + +/* HLC interrupt service routine */ +static irqreturn_t octeon_i2c_hlc_isr78(int irq, void *dev_id) +{ + struct octeon_i2c *i2c = dev_id; + + i2c->hlc_int_dis(i2c); wake_up(&i2c->queue); return IRQ_HANDLED; @@ -276,10 +347,10 @@ static int octeon_i2c_wait(struct octeon_i2c *i2c) { long time_left; - octeon_i2c_int_enable(i2c); + i2c->int_en(i2c); time_left = wait_event_timeout(i2c->queue, octeon_i2c_test_iflg(i2c), i2c->adap.timeout); - octeon_i2c_int_disable(i2c); + i2c->int_dis(i2c); if (!time_left) { dev_dbg(i2c->dev, "%s: timeout\n", __func__); return -ETIMEDOUT; @@ -413,11 +484,11 @@ static int octeon_i2c_hlc_wait(struct octeon_i2c *i2c) { int time_left; - octeon_i2c_hlc_int_enable(i2c); + i2c->hlc_int_en(i2c); time_left = wait_event_interruptible_timeout(i2c->queue, octeon_i2c_hlc_test_ready(i2c), i2c->adap.timeout); - octeon_i2c_int_disable(i2c); + i2c->hlc_int_dis(i2c); if (!time_left) { octeon_i2c_hlc_int_clear(i2c); dev_dbg(i2c->dev, "%s: timeout\n", __func__); @@ -969,14 +1040,26 @@ static struct i2c_adapter octeon_i2c_ops = { static int octeon_i2c_probe(struct platform_device *pdev) { struct device_node *node = pdev->dev.of_node; + int irq, result = 0, hlc_irq = 0; struct resource *res_mem; struct octeon_i2c *i2c; - int irq, result = 0; - - /* All adaptors have an irq. */ - irq = platform_get_irq(pdev, 0); - if (irq < 0) - return irq; + bool cn78xx_style; + + cn78xx_style = of_device_is_compatible(node, "cavium,octeon-7890-twsi"); + if (cn78xx_style) { + hlc_irq = platform_get_irq(pdev, 0); + if (hlc_irq < 0) + return hlc_irq; + + irq = platform_get_irq(pdev, 2); + if (irq < 0) + return irq; + } else { + /* All adaptors have an irq. */ + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + } i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL); if (!i2c) { @@ -1011,6 +1094,31 @@ static int octeon_i2c_probe(struct platform_device *pdev) i2c->irq = irq; + if (cn78xx_style) { + i2c->hlc_irq = hlc_irq; + + i2c->int_en = octeon_i2c_int_enable78; + i2c->int_dis = octeon_i2c_int_disable78; + i2c->hlc_int_en = octeon_i2c_hlc_int_enable78; + i2c->hlc_int_dis = octeon_i2c_hlc_int_disable78; + + irq_set_status_flags(i2c->irq, IRQ_NOAUTOEN); + irq_set_status_flags(i2c->hlc_irq, IRQ_NOAUTOEN); + + result = devm_request_irq(&pdev->dev, i2c->hlc_irq, + octeon_i2c_hlc_isr78, 0, + DRV_NAME, i2c); + if (result < 0) { + dev_err(i2c->dev, "failed to attach interrupt\n"); + goto out; + } + } else { + i2c->int_en = octeon_i2c_int_enable; + i2c->int_dis = octeon_i2c_int_disable; + i2c->hlc_int_en = octeon_i2c_hlc_int_enable; + i2c->hlc_int_dis = octeon_i2c_int_disable; + } + result = devm_request_irq(&pdev->dev, i2c->irq, octeon_i2c_isr, 0, DRV_NAME, i2c); if (result < 0) { @@ -1056,6 +1164,7 @@ static int octeon_i2c_remove(struct platform_device *pdev) static const struct of_device_id octeon_i2c_match[] = { { .compatible = "cavium,octeon-3860-twsi", }, + { .compatible = "cavium,octeon-7890-twsi", }, {}, }; MODULE_DEVICE_TABLE(of, octeon_i2c_match); -- 1.9.1