Messages in this thread Patch in this message | | | Date | Tue, 6 Sep 2022 15:24:58 +0300 | From | Andy Shevchenko <> | Subject | Re: [PATCH v2 5/5] gpio: pca953x: Add support for PCAL6534 |
| |
On Tue, Sep 06, 2022 at 09:28:19AM +0100, Martyn Welch wrote: > From: Martyn Welch <martyn.welch@collabora.com> > > Add support for the NXP PCAL6534. This device is broadly a 34-bit version > of the PCAL6524. However, whilst the registers are broadly what you'd > expect for a 34-bit version of the PCAL6524, the spacing of the registers > has been compacted. This has the unfortunate effect of breaking the bit > shift based mechanism that is employed to work out register locations used > by the other chips supported by this driver. To accommodate ths, callback > functions have been added to allow alterate implementations of > pca953x_recalc_addr() and pca953x_check_register() for the PCAL6534.
This looks much cleaner!
...
> @@ -107,6 +109,7 @@ static const struct i2c_device_id pca953x_id[] = { > { "tca9539", 16 | PCA953X_TYPE | PCA_INT, }, > { "tca9554", 8 | PCA953X_TYPE | PCA_INT, }, > { "xra1202", 8 | PCA953X_TYPE }, > + > { }
Missed Diodes?
> }; > MODULE_DEVICE_TABLE(i2c, pca953x_id);
...
> + u8 (*recalc_addr)(struct pca953x_chip *chip, int reg , int off); > + bool (*check_reg)(struct pca953x_chip *chip, unsigned int reg, > + u32 checkbank);
I would think of splitting this change. Like in a separate patch you simply create this interface and only add what you need in the next one.
...
> +static bool pcal6534_check_register(struct pca953x_chip *chip, unsigned int reg, > + u32 checkbank) > +{ > + int bank; > + int offset; > + > + if (reg > 0x2f) {
I guess code read and generation wise the
if (reg >= 0x30) {
is slightly better.
> + /* > + * Reserved block between 14h and 2Fh does not align on > + * expected bank boundaries like other devices. > + */ > + int temp = reg - 0x30; > + > + bank = temp / NBANK(chip); > + offset = temp - (bank * NBANK(chip));
Parentheses are not needed fur multiplication, but if you insist...
> + bank += 8;
> + } else if (reg > 0x53) {
In the similar way...
> + /* Handle lack of reserved registers after output port > + * configuration register to form a bank. > + */
Comment style
/* * Handle... */
> + int temp = reg - 0x54; > + > + bank = temp / NBANK(chip); > + offset = temp - (bank * NBANK(chip)); > + bank += 16; > + } else { > + bank = reg / NBANK(chip); > + offset = reg - (bank * NBANK(chip)); > + } > + > + /* Register is not in the matching bank. */ > + if (!(BIT(bank) & checkbank)) > + return false; > + > + /* Register is not within allowed range of bank. */ > + if (offset >= NBANK(chip)) > + return false; > + > + return true; > +}
...
> - u8 regaddr = pinctrl | addr | (off / BANK_SZ); > > - return regaddr; > + return pinctrl | addr | (off / BANK_SZ);
Stray change, or anything I have missed?
...
> +/* The PCAL6534 and compatible chips have altered bank alignment that doesn't > + * fit within the bit shifting scheme used for other devices. > + */
Comment style.
...
> @@ -1240,6 +1335,7 @@ static const struct of_device_id pca953x_dt_ids[] = { > > { .compatible = "nxp,pcal6416", .data = OF_953X(16, PCA_LATCH_INT), }, > { .compatible = "nxp,pcal6524", .data = OF_953X(24, PCA_LATCH_INT), }, > + { .compatible = "nxp,pcal6534", .data = OF_653X(34, PCA_LATCH_INT), }, > { .compatible = "nxp,pcal9535", .data = OF_953X(16, PCA_LATCH_INT), }, > { .compatible = "nxp,pcal9554b", .data = OF_953X( 8, PCA_LATCH_INT), }, > { .compatible = "nxp,pcal9555a", .data = OF_953X(16, PCA_LATCH_INT), },
Do you decide to drop Diodes compatible from the code?
-- With Best Regards, Andy Shevchenko
| |