From patchwork Mon Sep 3 11:52:19 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "AnilKumar, Chimata" X-Patchwork-Id: 1399571 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by patchwork2.kernel.org (Postfix) with ESMTP id 6F9EFDF280 for ; Mon, 3 Sep 2012 11:56:40 +0000 (UTC) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1T8VDi-0003dX-5D; Mon, 03 Sep 2012 11:53:34 +0000 Received: from arroyo.ext.ti.com ([192.94.94.40]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1T8VCo-0003Ej-Uy for linux-arm-kernel@lists.infradead.org; Mon, 03 Sep 2012 11:52:43 +0000 Received: from dbdp20.itg.ti.com ([172.24.170.38]) by arroyo.ext.ti.com (8.13.7/8.13.7) with ESMTP id q83BqX4h020178; Mon, 3 Sep 2012 06:52:34 -0500 Received: from DBDE70.ent.ti.com (localhost [127.0.0.1]) by dbdp20.itg.ti.com (8.13.8/8.13.8) with ESMTP id q83BqV2J004562; Mon, 3 Sep 2012 17:22:33 +0530 (IST) Received: from dbdp32.itg.ti.com (172.24.170.251) by dbde70.ent.ti.com (172.24.170.148) with Microsoft SMTP Server id 14.1.323.3; Mon, 3 Sep 2012 17:22:31 +0530 Received: from localhost.localdomain (dbdp20.itg.ti.com [172.24.170.38]) by dbdp32.itg.ti.com (8.13.8/8.13.8) with ESMTP id q83BqRMb019644; Mon, 3 Sep 2012 17:22:31 +0530 From: AnilKumar Ch To: , Subject: [PATCH 4/4] can: c_can: Add d_can suspend resume support Date: Mon, 3 Sep 2012 17:22:19 +0530 Message-ID: <1346673139-14540-5-git-send-email-anilkumar@ti.com> X-Mailer: git-send-email 1.7.0.4 In-Reply-To: <1346673139-14540-1-git-send-email-anilkumar@ti.com> References: <1346673139-14540-1-git-send-email-anilkumar@ti.com> MIME-Version: 1.0 X-Spam-Note: CRM114 invocation failed X-Spam-Score: -7.1 (-------) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-7.1 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at http://www.dnswl.org/, high trust [192.94.94.40 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -0.2 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: tony@atomide.com, linux-omap@vger.kernel.org, AnilKumar Ch , linux-arm-kernel@lists.infradead.org, linux-can@vger.kernel.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Adds suspend resume support to DCAN driver which enables DCAN power down mode bit (PDR). Then DCAN will ack the local power-down mode by setting PDA bit in STATUS register. Also adds a status flag to know the status of DCAN module, whether it is opened or not. Signed-off-by: AnilKumar Ch --- drivers/net/can/c_can/c_can.c | 78 ++++++++++++++++++++++++++++++++ drivers/net/can/c_can/c_can.h | 5 ++ drivers/net/can/c_can/c_can_platform.c | 70 ++++++++++++++++++++++++++-- 3 files changed, 150 insertions(+), 3 deletions(-) diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c index c175410..36d5db4 100644 --- a/drivers/net/can/c_can/c_can.c +++ b/drivers/net/can/c_can/c_can.c @@ -46,6 +46,9 @@ #define IF_ENUM_REG_LEN 11 #define C_CAN_IFACE(reg, iface) (C_CAN_IF1_##reg + (iface) * IF_ENUM_REG_LEN) +/* control extension register D_CAN specific */ +#define CONTROL_EX_PDR BIT(8) + /* control register */ #define CONTROL_TEST BIT(7) #define CONTROL_CCE BIT(6) @@ -65,6 +68,7 @@ #define TEST_BASIC BIT(2) /* status register */ +#define STATUS_PDA BIT(10) #define STATUS_BOFF BIT(7) #define STATUS_EWARN BIT(6) #define STATUS_EPASS BIT(5) @@ -164,6 +168,9 @@ /* minimum timeout for checking BUSY status */ #define MIN_TIMEOUT_VALUE 6 +/* Wait for ~1 sec for INIT bit */ +#define INIT_WAIT_COUNT 1000 + /* napi related */ #define C_CAN_NAPI_WEIGHT C_CAN_MSG_OBJ_RX_NUM @@ -1102,6 +1109,7 @@ static int c_can_open(struct net_device *dev) netif_start_queue(dev); + priv->is_opened = true; return 0; exit_irq_fail: @@ -1126,6 +1134,7 @@ static int c_can_close(struct net_device *dev) /* De-Initialize DCAN RAM */ c_can_reset_ram(priv, false); c_can_pm_runtime_put_sync(priv); + priv->is_opened = false; return 0; } @@ -1154,6 +1163,75 @@ struct net_device *alloc_c_can_dev(void) } EXPORT_SYMBOL_GPL(alloc_c_can_dev); +#ifdef CONFIG_PM +int c_can_power_down(struct net_device *dev) +{ + unsigned long time_out; + struct c_can_priv *priv = netdev_priv(dev); + + if (!priv->is_opened) + return 0; + + /* set `PDR` value so the device goes to power down mode */ + priv->write_reg(priv, C_CAN_CTRL_EX_REG, + priv->read_reg(priv, C_CAN_CTRL_EX_REG) | CONTROL_EX_PDR); + + /* Wait for the PDA bit to get set */ + time_out = jiffies + msecs_to_jiffies(INIT_WAIT_COUNT); + while (!(priv->read_reg(priv, C_CAN_STS_REG) & STATUS_PDA) && + time_after(time_out, jiffies)) + cpu_relax(); + + if (time_after(jiffies, time_out)) + return -ETIMEDOUT; + + c_can_stop(dev); + + /* De-initialize DCAN RAM */ + c_can_reset_ram(priv, false); + c_can_pm_runtime_put_sync(priv); + + return 0; +} +EXPORT_SYMBOL_GPL(c_can_power_down); + +int c_can_power_up(struct net_device *dev) +{ + unsigned long time_out; + struct c_can_priv *priv = netdev_priv(dev); + + if (!priv->is_opened) + return 0; + + c_can_pm_runtime_get_sync(priv); + /* Initialize DCAN RAM */ + c_can_reset_ram(priv, true); + + /* Clear PDR and INIT bits */ + priv->write_reg(priv, C_CAN_CTRL_EX_REG, + priv->read_reg(priv, C_CAN_CTRL_EX_REG) & ~CONTROL_EX_PDR); + priv->write_reg(priv, C_CAN_CTRL_REG, + priv->read_reg(priv, C_CAN_CTRL_REG) & ~CONTROL_INIT); + + /* Wait for the PDA bit to get clear */ + time_out = jiffies + msecs_to_jiffies(INIT_WAIT_COUNT); + while ((priv->read_reg(priv, C_CAN_STS_REG) & STATUS_PDA) && + time_after(time_out, jiffies)) + cpu_relax(); + + if (time_after(jiffies, time_out)) + return -ETIMEDOUT; + + c_can_start(dev); + + return 0; +} +EXPORT_SYMBOL_GPL(c_can_power_up); +#else +#define c_can_power_down NULL +#define c_can_power_up NULL +#endif + void free_c_can_dev(struct net_device *dev) { free_candev(dev); diff --git a/drivers/net/can/c_can/c_can.h b/drivers/net/can/c_can/c_can.h index 5f6339c..e5dd7ef 100644 --- a/drivers/net/can/c_can/c_can.h +++ b/drivers/net/can/c_can/c_can.h @@ -24,6 +24,7 @@ enum reg { C_CAN_CTRL_REG = 0, + C_CAN_CTRL_EX_REG, C_CAN_STS_REG, C_CAN_ERR_CNT_REG, C_CAN_BTR_REG, @@ -104,6 +105,7 @@ static const u16 reg_map_c_can[] = { static const u16 reg_map_d_can[] = { [C_CAN_CTRL_REG] = 0x00, + [C_CAN_CTRL_EX_REG] = 0x02, [C_CAN_STS_REG] = 0x04, [C_CAN_ERR_CNT_REG] = 0x08, [C_CAN_BTR_REG] = 0x0C, @@ -166,6 +168,7 @@ struct c_can_priv { unsigned int tx_echo; void *priv; /* for board-specific data */ u16 irqstatus; + bool is_opened; unsigned int instance; void (*ram_init) (unsigned int instance, bool enable); }; @@ -174,5 +177,7 @@ struct net_device *alloc_c_can_dev(void); void free_c_can_dev(struct net_device *dev); int register_c_can_dev(struct net_device *dev); void unregister_c_can_dev(struct net_device *dev); +int c_can_power_up(struct net_device *dev); +int c_can_power_down(struct net_device *dev); #endif /* C_CAN_H */ diff --git a/drivers/net/can/c_can/c_can_platform.c b/drivers/net/can/c_can/c_can_platform.c index c6963b2..65ec232 100644 --- a/drivers/net/can/c_can/c_can_platform.c +++ b/drivers/net/can/c_can/c_can_platform.c @@ -255,15 +255,79 @@ static int __devexit c_can_plat_remove(struct platform_device *pdev) return 0; } +#ifdef CONFIG_PM +static int c_can_suspend(struct platform_device *pdev, pm_message_t state) +{ + int ret; + struct net_device *ndev = platform_get_drvdata(pdev); + struct c_can_priv *priv = netdev_priv(ndev); + const struct platform_device_id *id = platform_get_device_id(pdev); + + if (id->driver_data != BOSCH_D_CAN) { + dev_warn(&pdev->dev, "Not supported\n"); + return 0; + } + + if (netif_running(ndev)) { + netif_stop_queue(ndev); + netif_device_detach(ndev); + } + + ret = c_can_power_down(ndev); + if (ret) { + dev_err(&pdev->dev, "failed to enter power down mode\n"); + return ret; + } + + priv->can.state = CAN_STATE_SLEEPING; + + return 0; +} + +static int c_can_resume(struct platform_device *pdev) +{ + int ret; + + struct net_device *ndev = platform_get_drvdata(pdev); + struct c_can_priv *priv = netdev_priv(ndev); + const struct platform_device_id *id = platform_get_device_id(pdev); + + if (id->driver_data != BOSCH_D_CAN) { + dev_warn(&pdev->dev, "Not supported\n"); + return 0; + } + + ret = c_can_power_up(ndev); + if (ret) { + dev_err(&pdev->dev, "Still in power down mode\n"); + return ret; + } + + priv->can.state = CAN_STATE_ERROR_ACTIVE; + + if (netif_running(ndev)) { + netif_device_attach(ndev); + netif_start_queue(ndev); + } + + return 0; +} +#else +#define c_can_suspend NULL +#define c_can_resume NULL +#endif + static struct platform_driver c_can_plat_driver = { .driver = { .name = KBUILD_MODNAME, .owner = THIS_MODULE, .of_match_table = of_match_ptr(c_can_of_table), }, - .probe = c_can_plat_probe, - .remove = __devexit_p(c_can_plat_remove), - .id_table = c_can_id_table, + .probe = c_can_plat_probe, + .remove = __devexit_p(c_can_plat_remove), + .suspend = c_can_suspend, + .resume = c_can_resume, + .id_table = c_can_id_table, }; module_platform_driver(c_can_plat_driver);