Hi Ahmed, Thanks for the review. I will take care of suggested changes in next version. Thanks, Jolly Shah > -----Original Message----- > From: Ahmed S. Darwish [mailto:darwish.07@xxxxxxxxx] > Sent: Tuesday, September 11, 2018 6:10 PM > To: Jolly Shah <JOLLYS@xxxxxxxxxx> > Cc: matthias.bgg@xxxxxxxxx; andy.gross@xxxxxxxxxx; shawnguo@xxxxxxxxxx; > geert+renesas@xxxxxxxxx; bjorn.andersson@xxxxxxxxxx; > sean.wang@xxxxxxxxxxxx; m.szyprowski@xxxxxxxxxxx; Michal Simek > <michals@xxxxxxxxxx>; robh+dt@xxxxxxxxxx; mark.rutland@xxxxxxx; Rajan > Vaja <RAJANV@xxxxxxxxxx>; devicetree@xxxxxxxxxxxxxxx; linux-arm- > kernel@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Rajan Vaja > <RAJANV@xxxxxxxxxx>; Jolly Shah <JOLLYS@xxxxxxxxxx> > Subject: Re: [PATCH v3 3/3] drivers: soc: xilinx: Add ZynqMP PM driver > > Hi! > > [ Thanks a lot for upstreaming this.. ] > > On Tue, Sep 11, 2018 at 02:34:57PM -0700, Jolly Shah wrote: > > From: Rajan Vaja <rajan.vaja@xxxxxxxxxx> > > > > Add ZynqMP PM driver. PM driver provides power management support for > > ZynqMP. > > > > Signed-off-by: Rajan Vaja <rajan.vaja@xxxxxxxxxx> > > Signed-off-by: Jolly Shah <jollys@xxxxxxxxxx> > > --- > > [...] > > > +static irqreturn_t zynqmp_pm_isr(int irq, void *data) { > > + u32 payload[CB_PAYLOAD_SIZE]; > > + > > + zynqmp_pm_get_callback_data(payload); > > + > > + /* First element is callback API ID, others are callback arguments */ > > + if (payload[0] == PM_INIT_SUSPEND_CB) { > > + if (work_pending(&zynqmp_pm_init_suspend_work- > >callback_work)) > > + goto done; > > + > > + /* Copy callback arguments into work's structure */ > > + memcpy(zynqmp_pm_init_suspend_work->args, &payload[1], > > + sizeof(zynqmp_pm_init_suspend_work->args)); > > + > > + queue_work(system_unbound_wq, > > + &zynqmp_pm_init_suspend_work->callback_work); > > We already have devm_request_threaded_irq() which can does this > automatically for us. > > Use that method to register the ISR instead, then if there's more work to do, just > do the memcpy and return IRQ_WAKE_THREAD. > > > + } > > + > > +done: > > + return IRQ_HANDLED; > > +} > > + > > +/** > > + * zynqmp_pm_init_suspend_work_fn() - Initialize suspend > > + * @work: Pointer to work_struct > > + * > > + * Bottom-half of PM callback IRQ handler. > > + */ > > +static void zynqmp_pm_init_suspend_work_fn(struct work_struct *work) > > +{ > > + struct zynqmp_pm_work_struct *pm_work = > > + container_of(work, struct zynqmp_pm_work_struct, > callback_work); > > + > > + if (pm_work->args[0] == > ZYNQMP_PM_SUSPEND_REASON_SYSTEM_SHUTDOWN) { > > we_really_seem_to_love_long_40_col_names_for_some_reason > > > + orderly_poweroff(true); > > + } else if (pm_work->args[0] == > > + ZYNQMP_PM_SUSPEND_REASON_POWER_UNIT_REQUEST) { > > Ditto > > [...] > > > +/** > > + * zynqmp_pm_sysfs_init() - Initialize PM driver sysfs interface > > + * @dev: Pointer to device structure > > + * > > + * Return: 0 on success, negative error code otherwise */ static int > > +zynqmp_pm_sysfs_init(struct device *dev) { > > + return sysfs_create_file(&dev->kobj, &dev_attr_suspend_mode.attr); } > > + > > Sysfs file is created in platform driver's probe(), but is not removed anywhere in > the code. > > What happens if this is built as a module? Am I missing something obvious? > > Moreover, what's the wisdom of creating a one-liner function with a huge six- > line comment that: > > a) _purely_ wraps sysfs_create_file(); no extra logic > b) is called only once > c) and not passed as a function pointer anywhere > > IMO Such one-liner translators obfuscate the code and review process with no > apparent gain.. > > > +/** > > + * zynqmp_pm_probe() - Probe existence of the PMU Firmware > > + * and initialize debugfs interface > > + * > > + * @pdev: Pointer to the platform_device structure > > + * > > + * Return: Returns 0 on success, negative error code otherwise */ > > Again, huge 8-line comment that provide no value. > > If anyone wants to know what a platform driver probe() does, he or she better > check the primary references at: > > - Documentation/driver-model/platform.txt > - include/linux/platform_device.h > > and not the comment above.. > > > +static int zynqmp_pm_probe(struct platform_device *pdev) { > > + int ret, irq; > > + u32 pm_api_version; > > + > > + const struct zynqmp_eemi_ops *eemi_ops = > zynqmp_pm_get_eemi_ops(); > > + > > + if (!eemi_ops || !eemi_ops->get_api_version || !eemi_ops- > >init_finalize) > > + return -ENXIO; > > + > > + eemi_ops->init_finalize(); > > + eemi_ops->get_api_version(&pm_api_version); > > + > > + /* Check PM API version number */ > > + if (pm_api_version < ZYNQMP_PM_VERSION) > > + return -ENODEV; > > + > > + irq = platform_get_irq(pdev, 0); > > + if (irq <= 0) > > + return -ENXIO; > > + > > + ret = devm_request_irq(&pdev->dev, irq, zynqmp_pm_isr, > IRQF_SHARED, > > + dev_name(&pdev->dev), pdev); > > + if (ret) { > > + dev_err(&pdev->dev, "request_irq '%d' failed with %d\n", > > + irq, ret); > > + return ret; > > + } > > + > > + zynqmp_pm_init_suspend_work = > > + devm_kzalloc(&pdev->dev, sizeof(struct > zynqmp_pm_work_struct), > > + GFP_KERNEL); > > + if (!zynqmp_pm_init_suspend_work) > > + return -ENOMEM; > > + > > + INIT_WORK(&zynqmp_pm_init_suspend_work->callback_work, > > + zynqmp_pm_init_suspend_work_fn); > > + > > Let's use devm_request_threaded_irq(). Then we can completely remove the > work_struct, INIT_WORK(), and queuue_work() bits. > > > + ret = zynqmp_pm_sysfs_init(&pdev->dev); > > + if (ret) { > > + dev_err(&pdev->dev, "unable to initialize sysfs interface\n"); > > + return ret; > > + } > > + > > + return ret; > > Just return 0 please. BTW ret was declared without initialization. > > > +} > > + > > +static const struct of_device_id pm_of_match[] = { > > + { .compatible = "xlnx,zynqmp-power", }, > > + { /* end of table */ }, > > +}; > > +MODULE_DEVICE_TABLE(of, pm_of_match); > > + > > +static struct platform_driver zynqmp_pm_platform_driver = { > > + .probe = zynqmp_pm_probe, > > + .driver = { > > + .name = "zynqmp_power", > > + .of_match_table = pm_of_match, > > + }, > > +}; > > .remove with a basic sysfs_remove_file() is needed. > > Thanks, > > -- > Darwi > http://darwish.chasingpointers.com
