From mboxrd@z Thu Jan 1 00:00:00 1970 From: Geert Uytterhoeven Subject: Re: [PATCH v5 3/3] i2c/busses/i2c-icy: Add LTC2990 present on 2019 board revision Date: Tue, 20 Aug 2019 11:18:36 +0200 Message-ID: References: <20190819121618.16557-1-max@enpas.org> <20190819121618.16557-3-max@enpas.org> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: <20190819121618.16557-3-max@enpas.org> Sender: linux-kernel-owner@vger.kernel.org To: Max Staudt Cc: Linux I2C , linux-hwmon@vger.kernel.org, Wolfram Sang , Jean Delvare , Guenter Roeck , Linux/m68k , Linux Kernel Mailing List , John Paul Adrian Glaubitz , Bartosz Golaszewski List-Id: linux-m68k@vger.kernel.org On Mon, Aug 19, 2019 at 2:17 PM Max Staudt wrote: > Since the 2019 a1k.org community re-print of these PCBs sports an > LTC2990 hwmon chip as an example use case, let this driver autoprobe > for that as well. If it is present, modprobing ltc2990 is sufficient. > > The property_entry enables the three additional inputs available on > this particular board: > > in1 will be the voltage of the 5V rail, divided by 2. > in2 will be the voltage of the 12V rail, divided by 4. > temp3 will be measured using a PCB loop next the chip. > > v5: Style > > v4: Style > Added other possible addresses for LTC2990. > > v3: Merged with initial LTC2990 support on ICY. > Moved defaults from platform_data to swnode. > Added note to Kconfig. > > Signed-off-by: Max Staudt Reviewed-by: Geert Uytterhoeven One comment below... > --- a/drivers/i2c/busses/i2c-icy.c > +++ b/drivers/i2c/busses/i2c-icy.c > @@ -141,6 +166,35 @@ static int icy_probe(struct zorro_dev *z, > dev_info(&z->dev, "ICY I2C controller at %pa, IRQ not implemented\n", > &z->resource.start); > > + /* > + * The 2019 a1k.org PCBs have an LTC2990 at 0x4c, so start > + * it automatically once ltc2990 is modprobed. > + * > + * in0 is the voltage of the internal 5V power supply. > + * temp1 is the temperature inside the chip. > + * > + * See property_entry above for in1, in2, temp3. > + */ > + new_fwnode = fwnode_create_software_node(icy_ltc2990_props, NULL); > + if (IS_ERR(new_fwnode)) { > + dev_info(&z->dev, "Failed to create fwnode for LTC2990, error: %ld\n", > + PTR_ERR(new_fwnode)); > + } else { > + /* > + * Store the fwnode so we can destroy it on .remove(). > + * Only store it on success, as fwnode_remove_software_node() > + * is NULL safe, but not PTR_ERR safe. > + */ > + i2c->ltc2990_fwnode = new_fwnode; > + ltc2990_info.fwnode = new_fwnode; > + > + i2c->ltc2990_client = > + i2c_new_probed_device(&i2c->adapter, > + <c2990_info, > + icy_ltc2990_addresses, > + NULL); > + } > + > return 0; > } Since commit d3e1b617ae20c459 ("i2c: allow specify device properties in i2c_board_info"), the properties could be provided by info->properties, too. However, according to the comments for device_add_properties(), this is valid only if there is a real firmware node present. If that is true, Max' use is correct, while e.g. commit 6a7836ba7fb4abf6 ("ARM: imx: pca100: use device properties for at24 eeprom") isn't? Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds