Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1168915AbcKALh5 (ORCPT ); Tue, 1 Nov 2016 07:37:57 -0400 Received: from mail-pf0-f193.google.com ([209.85.192.193]:36062 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1168327AbcKALhv (ORCPT ); Tue, 1 Nov 2016 07:37:51 -0400 Date: Tue, 1 Nov 2016 19:37:43 +0800 From: Peter Chen To: Yoshihiro Shimoda Cc: kishon@ti.com, gregkh@linuxfoundation.org, balbi@kernel.org, Peter.Chen@nxp.com, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, linux-renesas-soc@vger.kernel.org Subject: Re: [PATCH v2] phy: rcar-gen3-usb2: add sysfs for usb role swap Message-ID: <20161101113743.GC28525@b29397-desktop> References: <1477983718-4145-1-git-send-email-yoshihiro.shimoda.uh@renesas.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1477983718-4145-1-git-send-email-yoshihiro.shimoda.uh@renesas.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8566 Lines: 245 On Tue, Nov 01, 2016 at 04:01:58PM +0900, Yoshihiro Shimoda wrote: > This patch adds sysfs "otg_inputs" for usb role swap. This parameter > is write-only and if you use them as the following, you can swap > the usb role. > > For example: > 1) connect a usb cable using 2 salvator-x boards > 2) On A-device (as host), you input the following command: > # echo a_bus_req/ > /sys/devices/platform/soc/ee080200.usb-phy/otg_inputs > 3) On B-device (as peripheral), you input the following command: > # echo b_bus_req > /sys/devices/platform/soc/ee080200.usb-phy/otg_inputs > > Then, the A-device acts as a peripheral (A-peripheral) and the B-device > acts as a host (B-host). > Please note that A-device must input the following command if you > want the board to act as a host again. (even if you disconnect the usb > cable, since id state may be the same, the condition keeps "A-peripheral".) > # echo a_bus_drop > /sys/devices/platform/soc/ee080200.usb-phy/otg_inputs > > Also you can use the following command if you want the B-device board to > act as a peripheral again. > # echo b_bus_req/ > /sys/devices/platform/soc/ee080200.usb-phy/otg_inputs > > Signed-off-by: Yoshihiro Shimoda > --- > This patch is based on the latest linux-phy.git / next branch. > (commit id = 7809cd2ce6abd4f431e4b14e6b1276a7cc842ac4) > > Since this patch is related to usb, I added email addresses of Greg, Felipe, > Peter and USB ML as CC. (This patch doesn't use USB OTG FSM though.) > > Changed from v1: > - rebase the latest next branch. > > .../ABI/testing/sysfs-platform-phy-rcar-gen3-usb2 | 11 ++ > drivers/phy/phy-rcar-gen3-usb2.c | 124 ++++++++++++++++++++- > 2 files changed, 134 insertions(+), 1 deletion(-) > create mode 100644 Documentation/ABI/testing/sysfs-platform-phy-rcar-gen3-usb2 > > diff --git a/Documentation/ABI/testing/sysfs-platform-phy-rcar-gen3-usb2 b/Documentation/ABI/testing/sysfs-platform-phy-rcar-gen3-usb2 > new file mode 100644 > index 0000000..c7e715af > --- /dev/null > +++ b/Documentation/ABI/testing/sysfs-platform-phy-rcar-gen3-usb2 > @@ -0,0 +1,11 @@ > +What: /sys/devices/platform//otg-inputs > +Date: October 2016 > +KernelVersion: 4.10 > +Contact: Yoshihiro Shimoda > +Description: > + This write-only file changes the phy mode for role swap of usb. > + This file accepts the following strings: > + "a_bus_req/" - switching from A-Host to A-Peripheral > + "a_bus_drop" - switching from A-Peripheral to A-Host > + "b_bus_req" - switching from B-Peripheral to B-Host > + "b_bus_req/" - switching from B-Host to B-Peripheral Would you really care OTG FSM state machine? If not, you could just use "host" and "peripheral" to stand for current USB role, and implement role switch sysfs like: /sys/devices/platform//role. Peter > diff --git a/drivers/phy/phy-rcar-gen3-usb2.c b/drivers/phy/phy-rcar-gen3-usb2.c > index 3d97ead..80f5bcc 100644 > --- a/drivers/phy/phy-rcar-gen3-usb2.c > +++ b/drivers/phy/phy-rcar-gen3-usb2.c > @@ -70,6 +70,7 @@ > #define USB2_LINECTRL1_DP_RPD BIT(18) > #define USB2_LINECTRL1_DMRPD_EN BIT(17) > #define USB2_LINECTRL1_DM_RPD BIT(16) > +#define USB2_LINECTRL1_OPMODE_NODRV BIT(6) > > /* ADPCTRL */ > #define USB2_ADPCTRL_OTGSESSVLD BIT(20) > @@ -161,6 +162,43 @@ static void rcar_gen3_init_for_peri(struct rcar_gen3_chan *ch) > schedule_work(&ch->work); > } > > +static void rcar_gen3_init_for_b_host(struct rcar_gen3_chan *ch) > +{ > + void __iomem *usb2_base = ch->base; > + u32 val; > + > + val = readl(usb2_base + USB2_LINECTRL1); > + writel(val | USB2_LINECTRL1_OPMODE_NODRV, usb2_base + USB2_LINECTRL1); > + > + rcar_gen3_set_linectrl(ch, 1, 1); > + rcar_gen3_set_host_mode(ch, 1); > + rcar_gen3_enable_vbus_ctrl(ch, 0); > + > + val = readl(usb2_base + USB2_LINECTRL1); > + writel(val & ~USB2_LINECTRL1_OPMODE_NODRV, usb2_base + USB2_LINECTRL1); > +} > + > +static void rcar_gen3_init_for_a_peri(struct rcar_gen3_chan *ch) > +{ > + rcar_gen3_set_linectrl(ch, 0, 1); > + rcar_gen3_set_host_mode(ch, 0); > + rcar_gen3_enable_vbus_ctrl(ch, 1); > +} > + > +static void rcar_gen3_init_from_a_peri_to_a_host(struct rcar_gen3_chan *ch) > +{ > + void __iomem *usb2_base = ch->base; > + u32 val; > + > + val = readl(usb2_base + USB2_OBINTEN); > + writel(val & ~USB2_OBINT_BITS, usb2_base + USB2_OBINTEN); > + > + rcar_gen3_enable_vbus_ctrl(ch, 0); > + rcar_gen3_init_for_host(ch); > + > + writel(val | USB2_OBINT_BITS, usb2_base + USB2_OBINTEN); > +} > + > static bool rcar_gen3_check_id(struct rcar_gen3_chan *ch) > { > return !!(readl(ch->base + USB2_ADPCTRL) & USB2_ADPCTRL_IDDIG); > @@ -174,6 +212,71 @@ static void rcar_gen3_device_recognition(struct rcar_gen3_chan *ch) > rcar_gen3_init_for_peri(ch); > } > > +/* > + * The following table is a state transition for usb phy mode: > + * State Event Next state > + * disconnected: E1 a_host > + * E2 b_peripheral > + * A-Device - a_host: E2 b_peripheral > + * E3 disconnected > + * E4 a_suspend > + * A-Device - a_suspend: E2 b_peripheral > + * E3 disconnected > + * E5 a_host > + * E6 a_peripheral > + * A-Device - a_peripheral: E2 b_peripheral > + * E3 disconnected > + * E5 a_host > + * B-Device - b_peripheral: E3 disconnected > + * E7 b_wait_acon > + * B-Device - b_wait_acon E3 disconnected > + * E8 b_host > + * B-Device - b_host: E3 disconnected > + * E9 b_peripheral > + * Events: > + * E1: ID = 0 && Host detects D+ pull up, E2: ID = 1 && VBUS = 1 > + * E3: VBUS = 0 || ID is changed, E4: a_bus_req/ > + * E5: a_bus_drop, E6: Turns D+ pull up off > + * E7: b_bus_req, E8: Detects D+ pull up > + * E9: b_bus_req/ > + */ > +static ssize_t otg_inputs_store(struct device *dev, > + struct device_attribute *attr, > + const char *buf, size_t count) > +{ > + struct rcar_gen3_chan *ch = dev_get_drvdata(dev); > + bool is_host, is_b_device; > + > + if (!ch->has_otg || !ch->phy->init_count) > + return -EIO; > + > + is_b_device = rcar_gen3_check_id(ch); /* true = B-Device */ > + is_host = !(readl(ch->base + USB2_COMMCTRL) & USB2_COMMCTRL_OTG_PERI); > + > + if (!strncmp(buf, "a_bus_req/", strlen("a_bus_req/"))) { > + if (is_b_device) /* fail if B-device */ > + return -ENODEV; > + rcar_gen3_init_for_a_peri(ch); > + } else if (!strncmp(buf, "a_bus_drop", strlen("a_bus_drop"))) { > + if (is_b_device || is_host) /* fail if B-device or A-host */ > + return -ENODEV; > + rcar_gen3_init_from_a_peri_to_a_host(ch); > + } else if (!strncmp(buf, "b_bus_req/", strlen("b_bus_req/"))) { > + if (!is_b_device || !is_host) /* fail if A-device or B-peri */ > + return -ENODEV; > + rcar_gen3_init_for_peri(ch); > + } else if (!strncmp(buf, "b_bus_req", strlen("b_bus_req"))) { > + if (!is_b_device) /* fail if A-device */ > + return -ENODEV; > + rcar_gen3_init_for_b_host(ch); > + } else { > + return -EINVAL; > + } > + > + return count; > +} > +static DEVICE_ATTR_WO(otg_inputs); > + > static void rcar_gen3_init_otg(struct rcar_gen3_chan *ch) > { > void __iomem *usb2_base = ch->base; > @@ -351,21 +454,40 @@ static int rcar_gen3_phy_usb2_probe(struct platform_device *pdev) > channel->vbus = NULL; > } > > + platform_set_drvdata(pdev, channel); > phy_set_drvdata(channel->phy, channel); > > provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate); > - if (IS_ERR(provider)) > + if (IS_ERR(provider)) { > dev_err(dev, "Failed to register PHY provider\n"); > + } else if (channel->has_otg) { > + int ret; > + > + ret = device_create_file(dev, &dev_attr_otg_inputs); > + if (ret < 0) > + return ret; > + } > > return PTR_ERR_OR_ZERO(provider); > } > > +static int rcar_gen3_phy_usb2_remove(struct platform_device *pdev) > +{ > + struct rcar_gen3_chan *channel = platform_get_drvdata(pdev); > + > + if (channel->has_otg) > + device_remove_file(&pdev->dev, &dev_attr_otg_inputs); > + > + return 0; > +}; > + > static struct platform_driver rcar_gen3_phy_usb2_driver = { > .driver = { > .name = "phy_rcar_gen3_usb2", > .of_match_table = rcar_gen3_phy_usb2_match_table, > }, > .probe = rcar_gen3_phy_usb2_probe, > + .remove = rcar_gen3_phy_usb2_remove, > }; > module_platform_driver(rcar_gen3_phy_usb2_driver); > > -- > 1.9.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-usb" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Best Regards, Peter Chen