Re: [PATCH] misc/pca9552: Fix inverted input status

[Miles Glenn <milesg@linux.vnet.ibm.com>]

On Wed, 2023-10-11 at 16:27 +0200, Cédric Le Goater wrote:
> On 9/27/23 22:32, Glenn Miles wrote:
> > The pca9552 INPUT0 and INPUT1 registers are supposed to
> > hold the logical values of the LED pins.  A logical 0
> > should be seen in the INPUT0/1 registers for a pin when
> > its corresponding LSn bits are set to 0, which is also
> > the state needed for turning on an LED in a typical
> > usage scenario.  Existing code was doing the opposite
> > and setting INPUT0/1 bit to a 1 when the LSn bit was
> > set to 0, so this commit fixes that.
> > 
> > Signed-off-by: Glenn Miles <milesg@linux.vnet.ibm.com>
> 
> Looks OK to me.
> 
> May be you could mention that the ON/OFF values are reversed on
> the pca953x family. This is good to know if one wants to model
> these devices one day.
> 

Yep, I will do that.

Thanks,

Glenn

> Reviewed-by: C޸dric Le Goater <clg@kaod.org>
> 
> Thanks,
> 
> C.
> 
> 
> > ---
> >   hw/misc/pca9552.c          | 13 +++++++++----
> >   tests/qtest/pca9552-test.c |  6 +++---
> >   2 files changed, 12 insertions(+), 7 deletions(-)
> > 
> > diff --git a/hw/misc/pca9552.c b/hw/misc/pca9552.c
> > index fff19e369a..ad811fb249 100644
> > --- a/hw/misc/pca9552.c
> > +++ b/hw/misc/pca9552.c
> > @@ -112,13 +112,18 @@ static void
> > pca955x_update_pin_input(PCA955xState *s)
> >   
> >           switch (config) {
> >           case PCA9552_LED_ON:
> > -            qemu_set_irq(s->gpio[i], 1);
> > -            s->regs[input_reg] |= 1 << input_shift;
> > -            break;
> > -        case PCA9552_LED_OFF:
> > +            /* Pin is set to 0V to turn on LED */
> >               qemu_set_irq(s->gpio[i], 0);
> >               s->regs[input_reg] &= ~(1 << input_shift);
> >               break;
> > +        case PCA9552_LED_OFF:
> > +            /*
> > +             * Pin is set to Hi-Z to turn off LED and
> > +             * pullup sets it to a logical 1.
> > +             */
> > +            qemu_set_irq(s->gpio[i], 1);
> > +            s->regs[input_reg] |= 1 << input_shift;
> > +            break;
> >           case PCA9552_LED_PWM0:
> >           case PCA9552_LED_PWM1:
> >               /* TODO */
> > diff --git a/tests/qtest/pca9552-test.c b/tests/qtest/pca9552-
> > test.c
> > index d80ed93cd3..ccca2b3d91 100644
> > --- a/tests/qtest/pca9552-test.c
> > +++ b/tests/qtest/pca9552-test.c
> > @@ -60,7 +60,7 @@ static void send_and_receive(void *obj, void
> > *data, QGuestAllocator *alloc)
> >       g_assert_cmphex(value, ==, 0x55);
> >   
> >       value = i2c_get8(i2cdev, PCA9552_INPUT0);
> > -    g_assert_cmphex(value, ==, 0x0);
> > +    g_assert_cmphex(value, ==, 0xFF);
> >   
> >       pca9552_init(i2cdev);
> >   
> > @@ -68,13 +68,13 @@ static void send_and_receive(void *obj, void
> > *data, QGuestAllocator *alloc)
> >       g_assert_cmphex(value, ==, 0x54);
> >   
> >       value = i2c_get8(i2cdev, PCA9552_INPUT0);
> > -    g_assert_cmphex(value, ==, 0x01);
> > +    g_assert_cmphex(value, ==, 0xFE);
> >   
> >       value = i2c_get8(i2cdev, PCA9552_LS3);
> >       g_assert_cmphex(value, ==, 0x54);
> >   
> >       value = i2c_get8(i2cdev, PCA9552_INPUT1);
> > -    g_assert_cmphex(value, ==, 0x10);
> > +    g_assert_cmphex(value, ==, 0xEF);
> >   }
> >   
> >   static void pca9552_register_nodes(void)