Messages in this thread | | | From | Dong Aisheng-B29396 <> | Subject | RE: [RFC PATCH 2/3] pinctrl: imx: add pinmux-imx53 support | Date | Tue, 6 Dec 2011 07:21:36 +0000 |
| |
> -----Original Message----- > From: Guo Shawn-R65073 > Sent: Tuesday, December 06, 2011 2:58 PM > To: Dong Aisheng-B29396 > Cc: Sascha Hauer; Linus Walleij; linux-kernel@vger.kernel.org; linux-arm- > kernel@lists.infradead.org; linus.walleij@stericsson.com; Guo Shawn- > R65073; kernel@pengutronix.de > Subject: Re: [RFC PATCH 2/3] pinctrl: imx: add pinmux-imx53 support > > On Tue, Dec 06, 2011 at 01:54:35PM +0800, Dong Aisheng-B29396 wrote: > > > -----Original Message----- > > > From: Sascha Hauer [mailto:s.hauer@pengutronix.de] > > > Sent: Tuesday, December 06, 2011 5:19 AM > > > To: Linus Walleij > > > Cc: Dong Aisheng-B29396; linux-kernel@vger.kernel.org; linux-arm- > > > kernel@lists.infradead.org; linus.walleij@stericsson.com; Guo Shawn- > > > R65073; kernel@pengutronix.de > > > Subject: Re: [RFC PATCH 2/3] pinctrl: imx: add pinmux-imx53 support > > > > > > On Mon, Dec 05, 2011 at 05:57:42PM +0100, Linus Walleij wrote: > > > > On Sun, Dec 4, 2011 at 12:49 PM, Dong Aisheng > > > > <b29396@freescale.com> > > > wrote: > > > > > > > > > +enum imx_mx53_pads { > > > > > + MX53_GPIO_19 = 0, > > > > > + MX53_KEY_COL0 = 1, > > > > (...) > > > > > > > > First I thought it looked a bit strange since you needed enums for > > > > all pads but then I realized that your macros use the same > > > > enumerator name to name the pad and then it looks sort of clever. > > > > > > > > But maybe put in a comment about that here: > > > > > > > > > +/* Pad names for the pinmux subsystem */ > > > > > > > > Like this: > > > > > > > > /* > > > > * Pad names for the pinmux subsystem. > > > > * These pad names are constructed from the pin enumerator names > > > > * in the IMX_PINCTRL_PIN() macro. > > > > */ > > > > > > > > > +static const struct pinctrl_pin_desc mx53_pads[] = { > > > > > + IMX_PINCTRL_PIN(MX53_GPIO_19), > > > > > + IMX_PINCTRL_PIN(MX53_KEY_COL0), > > > > (...) > > > > > > > > > +/* mx53 pin groups and mux mode */ static const unsigned > > > > > +mx53_fec_pins[] = { > > > > > + MX53_FEC_MDC, > > > > > + MX53_FEC_MDIO, > > > > > + MX53_FEC_REF_CLK, > > > > > + MX53_FEC_RX_ER, > > > > > + MX53_FEC_CRS_DV, > > > > > + MX53_FEC_RXD1, > > > > > + MX53_FEC_RXD0, > > > > > + MX53_FEC_TX_EN, > > > > > + MX53_FEC_TXD1, > > > > > + MX53_FEC_TXD0, > > > > > +}; > > > > > > > > I understand this. > > > > > > > > > +static const unsigned mx53_fec_mux[] = { 0, 0, 0, 0, 0, 0, 0, > > > > > +0, 0, 0 }; > > > > > > > > But what is this? Just zeroes? Why? > > > > Especially with a const so they really cannot be anything else. > > > > The same pin (0) can only be enumerated once. > > > > > > > > > +static const unsigned mx53_sd1_pins[] = { > > > > > + MX53_SD1_CMD, > > > > > + MX53_SD1_CLK, > > > > > + MX53_SD1_DATA0, > > > > > + MX53_SD1_DATA1, > > > > > + MX53_SD1_DATA2, > > > > > + MX53_SD1_DATA3, > > > > > + > > > > > +}; > > > > > +static const unsigned mx53_sd1_mux[] = { 0, 0, 0, 0, 0, 0 }; > > > > > > > > And here again. > > > > > > > > > +static const unsigned mx53_sd3_pins[] = { > > > > > + MX53_PATA_DATA8, > > > > > + MX53_PATA_DATA9, > > > > > + MX53_PATA_DATA10, > > > > > + MX53_PATA_DATA11, > > > > > + MX53_PATA_DATA0, > > > > > + MX53_PATA_DATA1, > > > > > + MX53_PATA_DATA2, > > > > > + MX53_PATA_DATA3, > > > > > + MX53_PATA_IORDY, > > > > > + MX53_PATA_RESET_B, > > > > > + > > > > > +}; > > > > > +static const unsigned mx53_sd3_mux[] = { 4, 4, 4, 4, 4, 4, 4, > > > > > +4, 2, > > > > > +2 }; > > > > > > > > This also looks strange. Can you explain what these muxes are? > > > > > > Freescale has named the pins after their primary function which is > > > quite confusing. > > > > > > The above means: > > > > > > MX53_PATA_DATA8 -> mux mode 4 > > > MX53_PATA_DATA9 -> mux mode 4 > > > ... > > > > > > This brings me to the point that currently we have the pins > > > described as > > > > > > #define MX53_PAD_<name>__<function> > > > > > > which means that you don't have to look into the datasheet to get > > > the different options for a pin (and don't have a chance to get it > wrong). > > > I don't really want to lose this. > > > > > Obviously current used pin defines in that way is pretty good. > > And I also don't want to lose this. > > > > Actually I also have tried to see if we can reuse the current iomux-v3 > code. > > > > For current pinmux driver, one approach I can see is that define mux > > in enum for each pin like: > > > > enum MX53_PAD_GPIO_19_MUX { > > MX53_PAD_GPIO_19__KPP_COL_5, > > MX53_PAD_GPIO_19__GPIO4_5, > > MX53_PAD_GPIO_19__CCM_CLKO, > > MX53_PAD_GPIO_19__SPDIF_OUT1, > > MX53_PAD_GPIO_19__RTC_CE_RTC_EXT_TRIG2, > > MX53_PAD_GPIO_19__ECSPI1_RDY, > > MX53_PAD_GPIO_19__FEC_TDATA_3, > > MX53_PAD_GPIO_19__SRC_INT_BOOT, }; > > I would say, no, do not do that, because it simply does not worth. > Most of the definitions will probably never be used. > > IMO, we can just focus on the support for device tree case (imx6) for now. > With proper DT binding for pinctrl settled, all these data can go into DT. > For those non-DT cases, we may want to leave them as they are for now. >
Can current pinctrl framework support DT well? Linus, Can you help answer it or if you have a plan on DT support if it's still not ready?
I was ever thought it might not support DT that why I changed to run the driver for imx53 first.
> > > Then put them in a common file for each mx53 based board to use. > > > > Take uart1 as an example, it could be: > > static const unsigned mx53_uart1_pins[] = { > > MX53_CSI0_DAT10, > > MX53_CSI0_DAT11, > > }; > > > > static const unsigned mx53_uart1_mux[] = { > > MX53_CSI0_DAT10__UART1_TXD_MUX, > > MX53_CSI0_DAT11__UART1_RXD_MUX }; > > > > static const struct imx_pin_group mx53_pin_groups[] = { > > IMX_PIN_GROUP("uart1grp", mx53_uart1_pins, mx53_uart1_mux), }; > > > > The benefit is that it's very clear and good maintainable. > > The defect is it will increase the code size a lot by defining all > > pin's mux enum and each pin's mux array in board file. > > > > Do you think if it's ok or you have any better idea? > > > > Regards > > Dong Aisheng
-- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |