Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754981AbcDKOEm (ORCPT ); Mon, 11 Apr 2016 10:04:42 -0400 Received: from mail-wm0-f45.google.com ([74.125.82.45]:36928 "EHLO mail-wm0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753939AbcDKOEj (ORCPT ); Mon, 11 Apr 2016 10:04:39 -0400 Date: Mon, 11 Apr 2016 15:04:33 +0100 From: Lee Jones To: Tomeu Vizoso Cc: "linux-kernel@vger.kernel.org" , Sameer Nanda , Javier Martinez Canillas , Benson Leung , Enric =?iso-8859-1?Q?Balletb=F2?= , Vic Yang , Stephen Boyd , Vincent Palatin , Randall Spangler , Todd Broch , Gwendal Grignou , Vic Yang , Olof Johansson , linux-input@vger.kernel.org, Dmitry Torokhov Subject: Re: [RESEND PATCH v7 1/6] mfd: cros_ec: Add MKBP event support Message-ID: <20160411140433.GX8094@x1> References: <1459842789-13852-1-git-send-email-tomeu.vizoso@collabora.com> <1459842789-13852-2-git-send-email-tomeu.vizoso@collabora.com> <20160407152947.GD3323@x1> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 11395 Lines: 319 On Mon, 11 Apr 2016, Tomeu Vizoso wrote: > On 7 April 2016 at 17:29, Lee Jones wrote: > > On Tue, 05 Apr 2016, Tomeu Vizoso wrote: > > > >> From: Vic Yang > >> > >> Newer revisions of the ChromeOS EC add more events besides the keyboard > >> ones. So handle interrupts in the MFD driver and let consumers register > >> for notifications for the events they might care. > >> > >> To keep backward compatibility, if the EC doesn't support MKBP event, we > >> fall back to the old MKBP key matrix host command. > >> > >> Signed-off-by: Vic Yang > >> [bleung: fixup some context changes going from v3.14 to v3.18] > >> Signed-off-by: Benson Leung > >> [tomeu: adapted to changes in mainline (in power-supply and platform/chrome)] > >> Signed-off-by: Tomeu Vizoso > > > > I'm not interested in your BSP submission path. As far as I'm > > concerned *this* is the first submission. If these guys are happy > > with the patch, they can either choose to Ack or Review it. Drop the > > blurb in the middle. > > Ok. > > >> Cc: Randall Spangler > >> Cc: Vincent Palatin > >> --- > >> > >> Changes in v7: None > >> Changes in v6: None > >> Changes in v5: None > >> Changes in v4: > >> - Calculate correctly the size of the payloads in > >> cros_ec_get_host_command_version_mask. > >> > >> Changes in v3: > >> - Remove duplicated prototype of cros_ec_get_host_event. > >> > >> Changes in v2: > >> - Allocate enough for the structs in cros_ec_get_host_command_version_mask, > >> not their pointers. > >> - Allocate msg in the stack in get_next_event and > >> get_keyboard_state_event, as suggested by Gwendal. > >> > >> drivers/input/keyboard/cros_ec_keyb.c | 135 ++++++++------------------------ > >> drivers/mfd/cros_ec.c | 57 +++++++++++++- > >> drivers/platform/chrome/cros_ec_proto.c | 92 ++++++++++++++++++++++ > >> include/linux/mfd/cros_ec.h | 34 ++++++++ > >> include/linux/mfd/cros_ec_commands.h | 34 ++++++++ > > > > What are the *build time* dependencies that warrant all of these > > changes happening in one patch? > > We can split further the changes without breaking the builds, but > cros-ec functionality will be broken in between if both the mfd driver > and the input driver handle the same interrupt, which will hurt > bisectability. Then you need to mention that in the cover letter *after* you've split the patches out. That will inform us that the patches need to be taken together, massively reducing the chances of a fail. The chances that a) a bisect will fall exactly between the 2 patches and then b) the drivers try to handle the same interrupt at the same time are significantly small enough for us to take that risk. > >> 5 files changed, 245 insertions(+), 107 deletions(-) > > > > [...] > > > >> diff --git a/drivers/mfd/cros_ec.c b/drivers/mfd/cros_ec.c > >> index 0eee63542038..fbe78b819fdd 100644 > >> --- a/drivers/mfd/cros_ec.c > >> +++ b/drivers/mfd/cros_ec.c > >> @@ -23,6 +23,7 @@ > >> #include > >> #include > >> #include > >> +#include > >> > >> #define CROS_EC_DEV_EC_INDEX 0 > >> #define CROS_EC_DEV_PD_INDEX 1 > >> @@ -49,11 +50,28 @@ static const struct mfd_cell ec_pd_cell = { > >> .pdata_size = sizeof(pd_p), > >> }; > >> > >> +static irqreturn_t ec_irq_thread(int irq, void *data) > >> +{ > >> + struct cros_ec_device *ec_dev = data; > >> + int ret; > >> + > >> + if (device_may_wakeup(ec_dev->dev)) > >> + pm_wakeup_event(ec_dev->dev, 0); > >> + > >> + ret = cros_ec_get_next_event(ec_dev); > >> + if (ret > 0) > >> + blocking_notifier_call_chain(&ec_dev->event_notifier, > >> + 0, ec_dev); > >> + return IRQ_HANDLED; > >> +} > >> + > >> int cros_ec_register(struct cros_ec_device *ec_dev) > >> { > >> struct device *dev = ec_dev->dev; > >> int err = 0; > >> > >> + BLOCKING_INIT_NOTIFIER_HEAD(&ec_dev->event_notifier); > >> + > >> ec_dev->max_request = sizeof(struct ec_params_hello); > >> ec_dev->max_response = sizeof(struct ec_response_get_protocol_info); > >> ec_dev->max_passthru = 0; > >> @@ -70,13 +88,24 @@ int cros_ec_register(struct cros_ec_device *ec_dev) > >> > >> cros_ec_query_all(ec_dev); > >> > >> + if (ec_dev->irq) { > >> + err = request_threaded_irq(ec_dev->irq, NULL, ec_irq_thread, > >> + IRQF_TRIGGER_LOW | IRQF_ONESHOT, > >> + "chromeos-ec", ec_dev); > >> + if (err) { > >> + dev_err(dev, "request irq %d: error %d\n", > > > > This is an ugly error message. Write them like you (as I user) would > > like to see. I suggest using proper English and grammar. > > > > "Failed to request IRQ %d: %d", irq, err ? > > Sounds good. > > >> + ec_dev->irq, err); > >> + return err; > >> + } > >> + } > >> + > >> err = mfd_add_devices(ec_dev->dev, PLATFORM_DEVID_AUTO, &ec_cell, 1, > >> NULL, ec_dev->irq, NULL); > >> if (err) { > >> dev_err(dev, > >> "Failed to register Embedded Controller subdevice %d\n", > >> err); > >> - return err; > >> + goto fail_mfd; > >> } > >> > >> if (ec_dev->max_passthru) { > >> @@ -94,7 +123,7 @@ int cros_ec_register(struct cros_ec_device *ec_dev) > >> dev_err(dev, > >> "Failed to register Power Delivery subdevice %d\n", > >> err); > >> - return err; > >> + goto fail_mfd; > >> } > >> } > >> > >> @@ -103,13 +132,18 @@ int cros_ec_register(struct cros_ec_device *ec_dev) > >> if (err) { > >> mfd_remove_devices(dev); > >> dev_err(dev, "Failed to register sub-devices\n"); > >> - return err; > >> + goto fail_mfd; > >> } > >> } > >> > >> dev_info(dev, "Chrome EC device registered\n"); > >> > >> return 0; > >> + > >> +fail_mfd: > >> + if (ec_dev->irq) > >> + free_irq(ec_dev->irq, ec_dev); > >> + return err; > >> } > >> EXPORT_SYMBOL(cros_ec_register); > >> > >> @@ -136,13 +170,30 @@ int cros_ec_suspend(struct cros_ec_device *ec_dev) > >> } > >> EXPORT_SYMBOL(cros_ec_suspend); > >> > >> +static void cros_ec_drain_events(struct cros_ec_device *ec_dev) > >> +{ > >> + while (cros_ec_get_next_event(ec_dev) > 0) > >> + blocking_notifier_call_chain(&ec_dev->event_notifier, > >> + 1, ec_dev); > >> +} > >> + > >> int cros_ec_resume(struct cros_ec_device *ec_dev) > >> { > >> enable_irq(ec_dev->irq); > >> > >> + /* > >> + * In some case, we need to distinguish events that occur during > > > > s/case/cases/ > > > > s/distinguish/distinguish between/ > > Cool. > > >> diff --git a/include/linux/mfd/cros_ec.h b/include/linux/mfd/cros_ec.h > >> index a677c2bd485c..ddc935ef1911 100644 > >> --- a/include/linux/mfd/cros_ec.h > >> +++ b/include/linux/mfd/cros_ec.h > >> @@ -72,6 +72,24 @@ struct cros_ec_command { > >> uint8_t data[0]; > >> }; > >> > >> +/* > >> + * event_data is used by keyboard or event notifier: > >> + * event_data format: > >> + * If MKBP protocol is supported: > >> + * 0 1 > >> + * +-----------+-------------------------------- > >> + * | type | payload > >> + * +-----------+-------------------------------- > >> + * |HOST_EVENT | EVENT (32 bit) > >> + * |KEY_MATRIX | Keyboard keys pressed. > >> + * |SENSOR_FIFO| Sensors FIFO information. > >> + * > >> + * Otherwise: > >> + * 0 1 > >> + * +-----------+-------------------------------- > >> + * |Unused | Keyboard keys pressed. > >> + */ > > > > Personally, I don't think this documentation is required. But if you > > insist on supplying it, I think it'll be better placed near the > > 'struct ec_response_get_next_event' definition. > > I'm personally fine with leaving it out. > > >> /** > >> * struct cros_ec_device - Information about a ChromeOS EC device > >> * > >> @@ -107,6 +125,9 @@ struct cros_ec_command { > >> * should check msg.result for the EC's result code. > >> * @pkt_xfer: send packet to EC and get response > >> * @lock: one transaction at a time > >> + * @event_notifier: interrupt event notifier for transport devices. > >> + * @event_data: raw payload transferred with the MKBP event. > >> + * @event_size: size in bytes of the event data. > >> */ > >> struct cros_ec_device { > >> > >> @@ -135,6 +156,11 @@ struct cros_ec_device { > >> int (*pkt_xfer)(struct cros_ec_device *ec, > >> struct cros_ec_command *msg); > >> struct mutex lock; > >> + bool mkbp_event_supported; > > > > Did you document this? > > Oops. > > >> + struct blocking_notifier_head event_notifier; > >> + > >> + struct ec_response_get_next_event event_data; > >> + int event_size; > >> }; > >> > >> /* struct cros_ec_platform - ChromeOS EC platform information > >> @@ -252,6 +278,14 @@ int cros_ec_register(struct cros_ec_device *ec_dev); > >> */ > >> int cros_ec_query_all(struct cros_ec_device *ec_dev); > >> > >> +/** > >> + * cros_ec_get_next_event - Fetch next event from the ChromeOS EC > >> + * > >> + * @ec_dev: Device to fetch event from > >> + * @return 0 if ok, -ve on error > > > > I'd prefer easy to read/descriptive over trying to be smart. > > > > The 'return' value doesn' require a @. Instead, the return section > > should look like "Return: ". > > > > I suggest: "Return: 0 on success, Linux error number on failure" > > Sounds good to me. > > >> + */ > >> +int cros_ec_get_next_event(struct cros_ec_device *ec_dev); > >> + > >> /* sysfs stuff */ > >> extern struct attribute_group cros_ec_attr_group; > >> extern struct attribute_group cros_ec_lightbar_attr_group; > >> diff --git a/include/linux/mfd/cros_ec_commands.h b/include/linux/mfd/cros_ec_commands.h > >> index 13b630c10d4c..d86526f0bd8e 100644 > >> --- a/include/linux/mfd/cros_ec_commands.h > >> +++ b/include/linux/mfd/cros_ec_commands.h > >> @@ -1762,6 +1762,40 @@ struct ec_result_keyscan_seq_ctrl { > >> }; > >> } __packed; > >> > >> +/* > >> + * Get the next pending MKBP event. > >> + * > >> + * Returns EC_RES_UNAVAILABLE if there is no event pending. > >> + */ > > > > You're documenting this command as if it's a function. This command > > does nothing by it's self, rather it is supplied to a function call, > > which does the work. Similarly this command returns nothing, the > > device will provide the UNAVAILABLE return value. Please update the > > comment. > > I see. This was following the style of the existing command docs, so > it may end up being a bit surprising. > > Thanks a lot, > > Tomeu -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog