From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?Q?Andreas_F=c3=a4rber?= Subject: Re: [RFC] serial: sc16is7xx: Use DT sub-nodes for UART ports Date: Fri, 10 Aug 2018 19:45:42 +0200 Message-ID: <0aa77961-fe60-6afe-e6c5-d2db4250cb22@suse.de> References: <20180805232651.10605-1-afaerber@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Rob Herring Cc: SERIAL DRIVERS , Linux-MIPS , jringle@gridpoint.com, Michael Allwright , Jakub Kicinski , liuxuenetmail@gmail.com, Greg Kroah-Hartman , Jiri Slaby , "linux-kernel@vger.kernel.org" List-Id: linux-serial@vger.kernel.org Am 10.08.2018 um 19:34 schrieb Rob Herring: > On Sun, Aug 5, 2018 at 5:27 PM Andreas Färber wrote: >> >> This is to allow using serdev. >> >> Signed-off-by: Andreas Färber >> --- >> drivers/tty/serial/sc16is7xx.c | 25 +++++++++++++++++++++++++ >> 1 file changed, 25 insertions(+) >> >> diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c >> index 243c96025053..ad7267274f65 100644 >> --- a/drivers/tty/serial/sc16is7xx.c >> +++ b/drivers/tty/serial/sc16is7xx.c >> @@ -1213,9 +1213,31 @@ static int sc16is7xx_probe(struct device *dev, >> SC16IS7XX_IOCONTROL_SRESET_BIT); >> >> for (i = 0; i < devtype->nr_uart; ++i) { >> +#ifdef CONFIG_OF >> + struct device_node *np; >> + struct platform_device *pdev; >> + char name[6] = "uartx"; >> +#endif >> + >> s->p[i].line = i; >> /* Initialize port data */ >> +#ifdef CONFIG_OF >> + name[4] = '0' + i; >> + np = of_get_child_by_name(dev->of_node, name); >> + if (IS_ERR(np)) { >> + ret = PTR_ERR(np); >> + goto out_ports; >> + } >> + pdev = of_platform_device_create(np, NULL, dev); > > Ideally, you would use of_platform_default_populate here. I think > you'd have to add a compatible to the child nodes, but that wouldn't > be a bad thing. I could envision that the child nodes ultimately > become their own driver utilizing the standard 8250 driver and a > compatible string would be needed in that case. Separate compatibles would mean separate drivers. Unlike your DUART example this is not an MMIO device that we can easily split but a SPI slave (well, regmap due to some I2C models). I don't see how separate drivers could work, given that the whole spi_device has a single interrupt for all functions of this device. That left me with this ugly but working construct. Is the uartX naming correct, or should it be serialX? Regards, Andreas > > You'd then have to loop over each child of 'dev' instead of the DT nodes. > >> + if (IS_ERR(pdev)) { >> + ret = PTR_ERR(pdev); >> + goto out_ports; >> + } >> + platform_set_drvdata(pdev, dev_get_drvdata(dev)); >> + s->p[i].port.dev = &pdev->dev; >> +#else >> s->p[i].port.dev = dev; >> +#endif >> s->p[i].port.irq = irq; >> s->p[i].port.type = PORT_SC16IS7XX; >> s->p[i].port.fifosize = SC16IS7XX_FIFO_SIZE; -- SUSE Linux GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany GF: Felix Imendörffer, Jane Smithard, Graham Norton HRB 21284 (AG Nürnberg)