From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tien Hock Loh Subject: Re: [PATCH v8 2/2] drivers/gpio: Altera soft IP GPIO driver Date: Thu, 5 Feb 2015 02:32:02 -0800 Message-ID: <1423132322.1110.13.camel@ubuntu> References: <1419409345-8297-1-git-send-email-thloh@altera.com> <1419409345-8297-3-git-send-email-thloh@altera.com> <1419419050.6157.11.camel@perches.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Return-path: In-Reply-To: <1419419050.6157.11.camel-6d6DIl74uiNBDgjK7y7TUQ@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Joe Perches Cc: thloh.linux-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Linus Walleij , Alexandre Courbot , Grant Likely , Andrew Morton , "David S. Miller" , Greg Kroah-Hartman , Mauro Carvalho Chehab , Antti Palosaari , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-gpio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Dinh Nguyen List-Id: linux-gpio@vger.kernel.org On Wed, 2014-12-24 at 03:04 -0800, Joe Perches wrote: > On Wed, 2014-12-24 at 00:22 -0800, thloh-EIB2kfCEclfQT0dZR+AlfA@public.gmane.org wrote: > > Adds a new driver for Altera soft GPIO IP. The driver is able to > > do read/write and allows GPIO to be a interrupt controller. > > Some trivial comments, some not quite so trivial. > > > diff --git a/drivers/gpio/gpio-altera.c b/drivers/gpio/gpio-altera.c > [] > > +static int altera_gpio_irq_set_type(struct irq_data *d, > > + unsigned int type) > > +{ > > + struct altera_gpio_chip *altera_gc = irq_data_get_irq_chip_data(d); > > + > > + altera_gc = irq_data_get_irq_chip_data(d); > > I presume this multiple initialization of altera_gc > is unnecessary duplication. I'll remove this. > > > +static void altera_gpio_irq_edge_handler(unsigned int irq, > > + struct irq_desc *desc) > > +{ > > + struct altera_gpio_chip *altera_gc; > > + struct irq_chip *chip; > > + struct of_mm_gpio_chip *mm_gc; > > + unsigned long status; > > + int i; > > + > > + altera_gc = irq_desc_get_handler_data(desc); > > + chip = irq_desc_get_chip(desc); > > + mm_gc = &altera_gc->mmchip; > > + > > + chained_irq_enter(chip, desc); > > + > > + while ((status = > > + (readl(mm_gc->regs + ALTERA_GPIO_EDGE_CAP) & > > + readl(mm_gc->regs + ALTERA_GPIO_IRQ_MASK)))) { > > + writel(status, mm_gc->regs + ALTERA_GPIO_EDGE_CAP); > > + for_each_set_bit(i, &status, mm_gc->gc.ngpio) { > > + generic_handle_irq( > > + irq_find_mapping(altera_gc->mmchip.gc.irqdomain > > + , i)); > > That's kind of unpleasant to read. > It might be better to use a separate these statements > and use a temporary for irq_find_mapping() > OK I'll fix it. > > +static void altera_gpio_irq_leveL_high_handler(unsigned int irq, > > + struct irq_desc *desc) > > +{ > > + struct altera_gpio_chip *altera_gc; > > + struct irq_chip *chip; > > + struct of_mm_gpio_chip *mm_gc; > > + unsigned long status; > > + int i; > > + > > + altera_gc = irq_desc_get_handler_data(desc); > > + chip = irq_desc_get_chip(desc); > > + mm_gc = &altera_gc->mmchip; > > + > > + chained_irq_enter(chip, desc); > > + > > + status = readl(mm_gc->regs + ALTERA_GPIO_DATA); > > + status &= readl(mm_gc->regs + ALTERA_GPIO_IRQ_MASK); > > + > > + for_each_set_bit(i, &status, mm_gc->gc.ngpio) { > > + generic_handle_irq( > > + irq_find_mapping(altera_gc->mmchip.gc.irqdomain, i)); > > Maybe a temporary here too > Yup > > +int altera_gpio_probe(struct platform_device *pdev) > > +{ > > + struct device_node *node = pdev->dev.of_node; > > + int id, reg, ret; > > + struct altera_gpio_chip *altera_gc; > > + > > + altera_gc = devm_kzalloc(&pdev->dev, sizeof(*altera_gc), GFP_KERNEL); > > + > > + if (altera_gc == NULL) > > + return -ENOMEM; > > No blank line after the devm_kzalloc please and > if (!altera_gc) > is more common. > > OK noted. > > + if (altera_gc->interrupt_trigger == IRQ_TYPE_LEVEL_HIGH) { > > + gpiochip_set_chained_irqchip(&altera_gc->mmchip.gc, > > + &altera_irq_chip, > > + altera_gc->mapped_irq, > > + altera_gpio_irq_leveL_high_handler); > > + } else { > > + gpiochip_set_chained_irqchip(&altera_gc->mmchip.gc, > > + &altera_irq_chip, > > + altera_gc->mapped_irq, > > + altera_gpio_irq_edge_handler); > > + } > > Sometimes using a ?: ternary is smaller code > > gpiochip_set_chained_irqchip(&altera_gc->mmchip.gc, > &altera_irq_chip, > altera_gc->mapped_irq, > altera_gc->interrupt_trigger == IRQ_TYPE_LEVEL_HIGH ? > altera_gpio_irq_leveL_high_handler : > altera_gpio_irq_edge_handler); > > > Yup I'll fix it. Regards, Tien Hock Loh -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html