diff mbox series

[v3,02/16] i2c: have I2C receive operation return uint8_t

Message ID 20181126200435.23408-3-minyard@acm.org
State Superseded
Headers show
Series [v3,01/16] i2c: Split smbus into parts | expand

Commit Message

Corey Minyard Nov. 26, 2018, 8:04 p.m. UTC
From: Corey Minyard <cminyard@mvista.com>


It is never supposed to fail and cannot return an error, so just
have it return the proper type.  Have it return 0xff on nothing
available, since that's what would happen on a real bus.

Signed-off-by: Corey Minyard <cminyard@mvista.com>

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

---
 hw/arm/pxa2xx.c         |  2 +-
 hw/arm/tosa.c           |  4 ++--
 hw/arm/z2.c             |  2 +-
 hw/audio/wm8750.c       |  2 +-
 hw/display/sii9022.c    |  2 +-
 hw/display/ssd0303.c    |  4 ++--
 hw/gpio/max7310.c       |  2 +-
 hw/i2c/core.c           | 32 +++++++++++++-------------------
 hw/i2c/i2c-ddc.c        |  2 +-
 hw/i2c/smbus_slave.c    |  4 ++--
 hw/input/lm832x.c       |  2 +-
 hw/misc/pca9552.c       |  2 +-
 hw/misc/tmp105.c        |  2 +-
 hw/misc/tmp421.c        |  2 +-
 hw/nvram/eeprom_at24c.c |  4 ++--
 hw/timer/ds1338.c       |  2 +-
 hw/timer/m41t80.c       |  2 +-
 hw/timer/twl92230.c     |  2 +-
 include/hw/i2c/i2c.h    |  7 +++----
 19 files changed, 37 insertions(+), 44 deletions(-)

-- 
2.17.1

Comments

Philippe Mathieu-Daudé Nov. 26, 2018, 8:23 p.m. UTC | #1
Hi Corey,

On 26/11/18 21:04, minyard@acm.org wrote:
> From: Corey Minyard <cminyard@mvista.com>

> 

> It is never supposed to fail and cannot return an error, so just

> have it return the proper type.  Have it return 0xff on nothing

> available, since that's what would happen on a real bus.

> 

> Signed-off-by: Corey Minyard <cminyard@mvista.com>

> Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

> ---

>  hw/arm/pxa2xx.c         |  2 +-

>  hw/arm/tosa.c           |  4 ++--

>  hw/arm/z2.c             |  2 +-

>  hw/audio/wm8750.c       |  2 +-

>  hw/display/sii9022.c    |  2 +-

>  hw/display/ssd0303.c    |  4 ++--

>  hw/gpio/max7310.c       |  2 +-

>  hw/i2c/core.c           | 32 +++++++++++++-------------------

>  hw/i2c/i2c-ddc.c        |  2 +-

>  hw/i2c/smbus_slave.c    |  4 ++--

>  hw/input/lm832x.c       |  2 +-

>  hw/misc/pca9552.c       |  2 +-

>  hw/misc/tmp105.c        |  2 +-

>  hw/misc/tmp421.c        |  2 +-

>  hw/nvram/eeprom_at24c.c |  4 ++--

>  hw/timer/ds1338.c       |  2 +-

>  hw/timer/m41t80.c       |  2 +-

>  hw/timer/twl92230.c     |  2 +-

>  include/hw/i2c/i2c.h    |  7 +++----

>  19 files changed, 37 insertions(+), 44 deletions(-)

> 

> diff --git a/hw/arm/pxa2xx.c b/hw/arm/pxa2xx.c

> index f598a1c053..3d7c88910e 100644

> --- a/hw/arm/pxa2xx.c

> +++ b/hw/arm/pxa2xx.c

> @@ -1286,7 +1286,7 @@ static int pxa2xx_i2c_event(I2CSlave *i2c, enum i2c_event event)

>      return 0;

>  }

>  

> -static int pxa2xx_i2c_rx(I2CSlave *i2c)

> +static uint8_t pxa2xx_i2c_rx(I2CSlave *i2c)

>  {

>      PXA2xxI2CSlaveState *slave = PXA2XX_I2C_SLAVE(i2c);

>      PXA2xxI2CState *s = slave->host;

> diff --git a/hw/arm/tosa.c b/hw/arm/tosa.c

> index 7a925fa5e6..eef9d427e7 100644

> --- a/hw/arm/tosa.c

> +++ b/hw/arm/tosa.c

> @@ -197,10 +197,10 @@ static int tosa_dac_event(I2CSlave *i2c, enum i2c_event event)

>      return 0;

>  }

>  

> -static int tosa_dac_recv(I2CSlave *s)

> +static uint8_t tosa_dac_recv(I2CSlave *s)

>  {

>      printf("%s: recv not supported!!!\n", __func__);

> -    return -1;

> +    return 0xff;

>  }

>  

>  static void tosa_tg_init(PXA2xxState *cpu)

> diff --git a/hw/arm/z2.c b/hw/arm/z2.c

> index 697a822f1e..6f18d924df 100644

> --- a/hw/arm/z2.c

> +++ b/hw/arm/z2.c

> @@ -243,7 +243,7 @@ static int aer915_event(I2CSlave *i2c, enum i2c_event event)

>      return 0;

>  }

>  

> -static int aer915_recv(I2CSlave *slave)

> +static uint8_t aer915_recv(I2CSlave *slave)

>  {

>      AER915State *s = AER915(slave);

>      int retval = 0x00;

> diff --git a/hw/audio/wm8750.c b/hw/audio/wm8750.c

> index f4aa838f62..169b006ade 100644

> --- a/hw/audio/wm8750.c

> +++ b/hw/audio/wm8750.c

> @@ -561,7 +561,7 @@ static int wm8750_tx(I2CSlave *i2c, uint8_t data)

>      return 0;

>  }

>  

> -static int wm8750_rx(I2CSlave *i2c)

> +static uint8_t wm8750_rx(I2CSlave *i2c)

>  {

>      return 0x00;

>  }

> diff --git a/hw/display/sii9022.c b/hw/display/sii9022.c

> index eaf11a6e7b..9994385c35 100644

> --- a/hw/display/sii9022.c

> +++ b/hw/display/sii9022.c

> @@ -79,7 +79,7 @@ static int sii9022_event(I2CSlave *i2c, enum i2c_event event)

>      return 0;

>  }

>  

> -static int sii9022_rx(I2CSlave *i2c)

> +static uint8_t sii9022_rx(I2CSlave *i2c)

>  {

>      sii9022_state *s = SII9022(i2c);

>      uint8_t res = 0x00;

> diff --git a/hw/display/ssd0303.c b/hw/display/ssd0303.c

> index eb90ba26be..8edf34986c 100644

> --- a/hw/display/ssd0303.c

> +++ b/hw/display/ssd0303.c

> @@ -62,10 +62,10 @@ typedef struct {

>      uint8_t framebuffer[132*8];

>  } ssd0303_state;

>  

> -static int ssd0303_recv(I2CSlave *i2c)

> +static uint8_t ssd0303_recv(I2CSlave *i2c)

>  {

>      BADF("Reads not implemented\n");

> -    return -1;

> +    return 0xff;

>  }

>  

>  static int ssd0303_send(I2CSlave *i2c, uint8_t data)

> diff --git a/hw/gpio/max7310.c b/hw/gpio/max7310.c

> index a560e3afd2..f35a930276 100644

> --- a/hw/gpio/max7310.c

> +++ b/hw/gpio/max7310.c

> @@ -39,7 +39,7 @@ static void max7310_reset(DeviceState *dev)

>      s->command = 0x00;

>  }

>  

> -static int max7310_rx(I2CSlave *i2c)

> +static uint8_t max7310_rx(I2CSlave *i2c)

>  {

>      MAX7310State *s = MAX7310(i2c);

>  

> diff --git a/hw/i2c/core.c b/hw/i2c/core.c

> index b54725985a..15237ad073 100644

> --- a/hw/i2c/core.c

> +++ b/hw/i2c/core.c

> @@ -191,23 +191,17 @@ int i2c_send_recv(I2CBus *bus, uint8_t *data, bool send)


i2c_send_recv() could benefit the same improvement.

>          }

>          return ret ? -1 : 0;

>      } else {

> -        if ((QLIST_EMPTY(&bus->current_devs)) || (bus->broadcast)) {

> -            return -1;

> -        }

> -

> -        sc = I2C_SLAVE_GET_CLASS(QLIST_FIRST(&bus->current_devs)->elt);

> -        if (sc->recv) {

> -            s = QLIST_FIRST(&bus->current_devs)->elt;

> -            ret = sc->recv(s);

> -            trace_i2c_recv(s->address, ret);

> -            if (ret < 0) {

> -                return ret;

> -            } else {

> -                *data = ret;

> -                return 0;

> +        ret = 0xff;

> +        if (!QLIST_EMPTY(&bus->current_devs) && !bus->broadcast) {

> +            sc = I2C_SLAVE_GET_CLASS(QLIST_FIRST(&bus->current_devs)->elt);

> +            if (sc->recv) {

> +                s = QLIST_FIRST(&bus->current_devs)->elt;

> +                ret = sc->recv(s);

> +                trace_i2c_recv(s->address, ret);

>              }

>          }

> -        return -1;

> +        *data = ret;

> +        return 0;

>      }

>  }

>  

> @@ -216,12 +210,12 @@ int i2c_send(I2CBus *bus, uint8_t data)

>      return i2c_send_recv(bus, &data, true);

>  }

>  

> -int i2c_recv(I2CBus *bus)

> +uint8_t i2c_recv(I2CBus *bus)

>  {

> -    uint8_t data;

> -    int ret = i2c_send_recv(bus, &data, false);

> +    uint8_t data = 0xff;

>  

> -    return ret < 0 ? ret : data;

> +    i2c_send_recv(bus, &data, false);

> +    return data;

>  }

>  

>  void i2c_nack(I2CBus *bus)

> diff --git a/hw/i2c/i2c-ddc.c b/hw/i2c/i2c-ddc.c

> index be34fe072c..95325358db 100644

> --- a/hw/i2c/i2c-ddc.c

> +++ b/hw/i2c/i2c-ddc.c

> @@ -51,7 +51,7 @@ static int i2c_ddc_event(I2CSlave *i2c, enum i2c_event event)

>      return 0;

>  }

>  

> -static int i2c_ddc_rx(I2CSlave *i2c)

> +static uint8_t i2c_ddc_rx(I2CSlave *i2c)

>  {

>      I2CDDCState *s = I2CDDC(i2c);

>  

> diff --git a/hw/i2c/smbus_slave.c b/hw/i2c/smbus_slave.c

> index 1e734752d7..549e7ae933 100644

> --- a/hw/i2c/smbus_slave.c

> +++ b/hw/i2c/smbus_slave.c

> @@ -156,11 +156,11 @@ static int smbus_i2c_event(I2CSlave *s, enum i2c_event event)

>      return 0;

>  }

>  

> -static int smbus_i2c_recv(I2CSlave *s)

> +static uint8_t smbus_i2c_recv(I2CSlave *s)

>  {

>      SMBusDevice *dev = SMBUS_DEVICE(s);

>      SMBusDeviceClass *sc = SMBUS_DEVICE_GET_CLASS(dev);

> -    int ret;

> +    uint8_t ret;

>  

>      switch (dev->mode) {

>      case SMBUS_RECV_BYTE:

> diff --git a/hw/input/lm832x.c b/hw/input/lm832x.c

> index 74da30d9ca..9ae037953d 100644

> --- a/hw/input/lm832x.c

> +++ b/hw/input/lm832x.c

> @@ -401,7 +401,7 @@ static int lm_i2c_event(I2CSlave *i2c, enum i2c_event event)

>      return 0;

>  }

>  

> -static int lm_i2c_rx(I2CSlave *i2c)

> +static uint8_t lm_i2c_rx(I2CSlave *i2c)

>  {

>      LM823KbdState *s = LM8323(i2c);

>  

> diff --git a/hw/misc/pca9552.c b/hw/misc/pca9552.c

> index 9775d5274a..7325d3f287 100644

> --- a/hw/misc/pca9552.c

> +++ b/hw/misc/pca9552.c

> @@ -115,7 +115,7 @@ static void pca9552_autoinc(PCA9552State *s)

>      }

>  }

>  

> -static int pca9552_recv(I2CSlave *i2c)

> +static uint8_t pca9552_recv(I2CSlave *i2c)

>  {

>      PCA9552State *s = PCA9552(i2c);

>      uint8_t ret;

> diff --git a/hw/misc/tmp105.c b/hw/misc/tmp105.c

> index 0918f3a6ea..a4cae665b7 100644

> --- a/hw/misc/tmp105.c

> +++ b/hw/misc/tmp105.c

> @@ -147,7 +147,7 @@ static void tmp105_write(TMP105State *s)

>      }

>  }

>  

> -static int tmp105_rx(I2CSlave *i2c)

> +static uint8_t tmp105_rx(I2CSlave *i2c)

>  {

>      TMP105State *s = TMP105(i2c);

>  

> diff --git a/hw/misc/tmp421.c b/hw/misc/tmp421.c

> index c234044305..a75eb994a8 100644

> --- a/hw/misc/tmp421.c

> +++ b/hw/misc/tmp421.c

> @@ -249,7 +249,7 @@ static void tmp421_write(TMP421State *s)

>      }

>  }

>  

> -static int tmp421_rx(I2CSlave *i2c)

> +static uint8_t tmp421_rx(I2CSlave *i2c)

>  {

>      TMP421State *s = TMP421(i2c);

>  

> diff --git a/hw/nvram/eeprom_at24c.c b/hw/nvram/eeprom_at24c.c

> index 27cd01e615..d1456dafbd 100644

> --- a/hw/nvram/eeprom_at24c.c

> +++ b/hw/nvram/eeprom_at24c.c

> @@ -74,10 +74,10 @@ int at24c_eeprom_event(I2CSlave *s, enum i2c_event event)

>  }

>  

>  static

> -int at24c_eeprom_recv(I2CSlave *s)

> +uint8_t at24c_eeprom_recv(I2CSlave *s)

>  {

>      EEPROMState *ee = AT24C_EE(s);

> -    int ret;

> +    uint8_t ret;

>  

>      ret = ee->mem[ee->cur];

>  

> diff --git a/hw/timer/ds1338.c b/hw/timer/ds1338.c

> index 3849b74a68..03da75486b 100644

> --- a/hw/timer/ds1338.c

> +++ b/hw/timer/ds1338.c

> @@ -117,7 +117,7 @@ static int ds1338_event(I2CSlave *i2c, enum i2c_event event)

>      return 0;

>  }

>  

> -static int ds1338_recv(I2CSlave *i2c)

> +static uint8_t ds1338_recv(I2CSlave *i2c)

>  {

>      DS1338State *s = DS1338(i2c);

>      uint8_t res;

> diff --git a/hw/timer/m41t80.c b/hw/timer/m41t80.c

> index 734d7d95fc..c45b9297d8 100644

> --- a/hw/timer/m41t80.c

> +++ b/hw/timer/m41t80.c

> @@ -40,7 +40,7 @@ static int m41t80_send(I2CSlave *i2c, uint8_t data)

>      return 0;

>  }

>  

> -static int m41t80_recv(I2CSlave *i2c)

> +static uint8_t m41t80_recv(I2CSlave *i2c)

>  {

>      M41t80State *s = M41T80(i2c);

>      struct tm now;

> diff --git a/hw/timer/twl92230.c b/hw/timer/twl92230.c

> index 3b43b46199..659b216dca 100644

> --- a/hw/timer/twl92230.c

> +++ b/hw/timer/twl92230.c

> @@ -737,7 +737,7 @@ static int menelaus_tx(I2CSlave *i2c, uint8_t data)

>      return 0;

>  }

>  

> -static int menelaus_rx(I2CSlave *i2c)

> +static uint8_t menelaus_rx(I2CSlave *i2c)

>  {

>      MenelausState *s = TWL92230(i2c);

>  

> diff --git a/include/hw/i2c/i2c.h b/include/hw/i2c/i2c.h

> index 5dc166158b..75c5bd638b 100644

> --- a/include/hw/i2c/i2c.h

> +++ b/include/hw/i2c/i2c.h

> @@ -33,10 +33,9 @@ typedef struct I2CSlaveClass {

>  

>      /*

>       * Slave to master.  This cannot fail, the device should always

> -     * return something here.  Negative values probably result in 0xff

> -     * and a possible log from the driver, and shouldn't be used.

> +     * return something here.


Maybe use simple comment as "Master receives the data sent by the Slave"

>       */

> -    int (*recv)(I2CSlave *s);

> +    uint8_t (*recv)(I2CSlave *s);

>  

>      /*

>       * Notify the slave of a bus state change.  For start event,

> @@ -78,7 +77,7 @@ void i2c_end_transfer(I2CBus *bus);

>  void i2c_nack(I2CBus *bus);

>  int i2c_send_recv(I2CBus *bus, uint8_t *data, bool send);

>  int i2c_send(I2CBus *bus, uint8_t data);

> -int i2c_recv(I2CBus *bus);

> +uint8_t i2c_recv(I2CBus *bus);

>  

>  DeviceState *i2c_create_slave(I2CBus *bus, const char *name, uint8_t addr);

>  


Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Corey Minyard Nov. 27, 2018, 12:14 a.m. UTC | #2
On 11/26/18 2:23 PM, Philippe Mathieu-Daudé wrote:
> Hi Corey,

>

> On 26/11/18 21:04, minyard@acm.org wrote:

>> From: Corey Minyard <cminyard@mvista.com>

>>

>> It is never supposed to fail and cannot return an error, so just

>> have it return the proper type.  Have it return 0xff on nothing

>> available, since that's what would happen on a real bus.

>>

>> Signed-off-by: Corey Minyard <cminyard@mvista.com>

>> Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

>> ---

>>   hw/arm/pxa2xx.c         |  2 +-

>>   hw/arm/tosa.c           |  4 ++--

>>   hw/arm/z2.c             |  2 +-

>>   hw/audio/wm8750.c       |  2 +-

>>   hw/display/sii9022.c    |  2 +-

>>   hw/display/ssd0303.c    |  4 ++--

>>   hw/gpio/max7310.c       |  2 +-

>>   hw/i2c/core.c           | 32 +++++++++++++-------------------

>>   hw/i2c/i2c-ddc.c        |  2 +-

>>   hw/i2c/smbus_slave.c    |  4 ++--

>>   hw/input/lm832x.c       |  2 +-

>>   hw/misc/pca9552.c       |  2 +-

>>   hw/misc/tmp105.c        |  2 +-

>>   hw/misc/tmp421.c        |  2 +-

>>   hw/nvram/eeprom_at24c.c |  4 ++--

>>   hw/timer/ds1338.c       |  2 +-

>>   hw/timer/m41t80.c       |  2 +-

>>   hw/timer/twl92230.c     |  2 +-

>>   include/hw/i2c/i2c.h    |  7 +++----

>>   19 files changed, 37 insertions(+), 44 deletions(-)

>>

>> diff --git a/hw/arm/pxa2xx.c b/hw/arm/pxa2xx.c

>> index f598a1c053..3d7c88910e 100644

>> --- a/hw/arm/pxa2xx.c

>> +++ b/hw/arm/pxa2xx.c

>> @@ -1286,7 +1286,7 @@ static int pxa2xx_i2c_event(I2CSlave *i2c, enum i2c_event event)

>>       return 0;

>>   }

>>   

>> -static int pxa2xx_i2c_rx(I2CSlave *i2c)

>> +static uint8_t pxa2xx_i2c_rx(I2CSlave *i2c)

>>   {

>>       PXA2xxI2CSlaveState *slave = PXA2XX_I2C_SLAVE(i2c);

>>       PXA2xxI2CState *s = slave->host;

>> diff --git a/hw/arm/tosa.c b/hw/arm/tosa.c

>> index 7a925fa5e6..eef9d427e7 100644

>> --- a/hw/arm/tosa.c

>> +++ b/hw/arm/tosa.c

>> @@ -197,10 +197,10 @@ static int tosa_dac_event(I2CSlave *i2c, enum i2c_event event)

>>       return 0;

>>   }

>>   

>> -static int tosa_dac_recv(I2CSlave *s)

>> +static uint8_t tosa_dac_recv(I2CSlave *s)

>>   {

>>       printf("%s: recv not supported!!!\n", __func__);

>> -    return -1;

>> +    return 0xff;

>>   }

>>   

>>   static void tosa_tg_init(PXA2xxState *cpu)

>> diff --git a/hw/arm/z2.c b/hw/arm/z2.c

>> index 697a822f1e..6f18d924df 100644

>> --- a/hw/arm/z2.c

>> +++ b/hw/arm/z2.c

>> @@ -243,7 +243,7 @@ static int aer915_event(I2CSlave *i2c, enum i2c_event event)

>>       return 0;

>>   }

>>   

>> -static int aer915_recv(I2CSlave *slave)

>> +static uint8_t aer915_recv(I2CSlave *slave)

>>   {

>>       AER915State *s = AER915(slave);

>>       int retval = 0x00;

>> diff --git a/hw/audio/wm8750.c b/hw/audio/wm8750.c

>> index f4aa838f62..169b006ade 100644

>> --- a/hw/audio/wm8750.c

>> +++ b/hw/audio/wm8750.c

>> @@ -561,7 +561,7 @@ static int wm8750_tx(I2CSlave *i2c, uint8_t data)

>>       return 0;

>>   }

>>   

>> -static int wm8750_rx(I2CSlave *i2c)

>> +static uint8_t wm8750_rx(I2CSlave *i2c)

>>   {

>>       return 0x00;

>>   }

>> diff --git a/hw/display/sii9022.c b/hw/display/sii9022.c

>> index eaf11a6e7b..9994385c35 100644

>> --- a/hw/display/sii9022.c

>> +++ b/hw/display/sii9022.c

>> @@ -79,7 +79,7 @@ static int sii9022_event(I2CSlave *i2c, enum i2c_event event)

>>       return 0;

>>   }

>>   

>> -static int sii9022_rx(I2CSlave *i2c)

>> +static uint8_t sii9022_rx(I2CSlave *i2c)

>>   {

>>       sii9022_state *s = SII9022(i2c);

>>       uint8_t res = 0x00;

>> diff --git a/hw/display/ssd0303.c b/hw/display/ssd0303.c

>> index eb90ba26be..8edf34986c 100644

>> --- a/hw/display/ssd0303.c

>> +++ b/hw/display/ssd0303.c

>> @@ -62,10 +62,10 @@ typedef struct {

>>       uint8_t framebuffer[132*8];

>>   } ssd0303_state;

>>   

>> -static int ssd0303_recv(I2CSlave *i2c)

>> +static uint8_t ssd0303_recv(I2CSlave *i2c)

>>   {

>>       BADF("Reads not implemented\n");

>> -    return -1;

>> +    return 0xff;

>>   }

>>   

>>   static int ssd0303_send(I2CSlave *i2c, uint8_t data)

>> diff --git a/hw/gpio/max7310.c b/hw/gpio/max7310.c

>> index a560e3afd2..f35a930276 100644

>> --- a/hw/gpio/max7310.c

>> +++ b/hw/gpio/max7310.c

>> @@ -39,7 +39,7 @@ static void max7310_reset(DeviceState *dev)

>>       s->command = 0x00;

>>   }

>>   

>> -static int max7310_rx(I2CSlave *i2c)

>> +static uint8_t max7310_rx(I2CSlave *i2c)

>>   {

>>       MAX7310State *s = MAX7310(i2c);

>>   

>> diff --git a/hw/i2c/core.c b/hw/i2c/core.c

>> index b54725985a..15237ad073 100644

>> --- a/hw/i2c/core.c

>> +++ b/hw/i2c/core.c

>> @@ -191,23 +191,17 @@ int i2c_send_recv(I2CBus *bus, uint8_t *data, bool send)

> i2c_send_recv() could benefit the same improvement.

>

I thought some about that, but the send function has to be able to return -1
for a NACK.  It would be nice to have separate send and recv functions, but
several host devices use i2c_send_recv() directly.


>>           }

>>           return ret ? -1 : 0;

>>       } else {

>> -        if ((QLIST_EMPTY(&bus->current_devs)) || (bus->broadcast)) {

>> -            return -1;

>> -        }

>> -

>> -        sc = I2C_SLAVE_GET_CLASS(QLIST_FIRST(&bus->current_devs)->elt);

>> -        if (sc->recv) {

>> -            s = QLIST_FIRST(&bus->current_devs)->elt;

>> -            ret = sc->recv(s);

>> -            trace_i2c_recv(s->address, ret);

>> -            if (ret < 0) {

>> -                return ret;

>> -            } else {

>> -                *data = ret;

>> -                return 0;

>> +        ret = 0xff;

>> +        if (!QLIST_EMPTY(&bus->current_devs) && !bus->broadcast) {

>> +            sc = I2C_SLAVE_GET_CLASS(QLIST_FIRST(&bus->current_devs)->elt);

>> +            if (sc->recv) {

>> +                s = QLIST_FIRST(&bus->current_devs)->elt;

>> +                ret = sc->recv(s);

>> +                trace_i2c_recv(s->address, ret);

>>               }

>>           }

>> -        return -1;

>> +        *data = ret;

>> +        return 0;

>>       }

>>   }

>>   

>> @@ -216,12 +210,12 @@ int i2c_send(I2CBus *bus, uint8_t data)

>>       return i2c_send_recv(bus, &data, true);

>>   }

>>   

>> -int i2c_recv(I2CBus *bus)

>> +uint8_t i2c_recv(I2CBus *bus)

>>   {

>> -    uint8_t data;

>> -    int ret = i2c_send_recv(bus, &data, false);

>> +    uint8_t data = 0xff;

>>   

>> -    return ret < 0 ? ret : data;

>> +    i2c_send_recv(bus, &data, false);

>> +    return data;

>>   }

>>   

>>   void i2c_nack(I2CBus *bus)

>> diff --git a/hw/i2c/i2c-ddc.c b/hw/i2c/i2c-ddc.c

>> index be34fe072c..95325358db 100644

>> --- a/hw/i2c/i2c-ddc.c

>> +++ b/hw/i2c/i2c-ddc.c

>> @@ -51,7 +51,7 @@ static int i2c_ddc_event(I2CSlave *i2c, enum i2c_event event)

>>       return 0;

>>   }

>>   

>> -static int i2c_ddc_rx(I2CSlave *i2c)

>> +static uint8_t i2c_ddc_rx(I2CSlave *i2c)

>>   {

>>       I2CDDCState *s = I2CDDC(i2c);

>>   

>> diff --git a/hw/i2c/smbus_slave.c b/hw/i2c/smbus_slave.c

>> index 1e734752d7..549e7ae933 100644

>> --- a/hw/i2c/smbus_slave.c

>> +++ b/hw/i2c/smbus_slave.c

>> @@ -156,11 +156,11 @@ static int smbus_i2c_event(I2CSlave *s, enum i2c_event event)

>>       return 0;

>>   }

>>   

>> -static int smbus_i2c_recv(I2CSlave *s)

>> +static uint8_t smbus_i2c_recv(I2CSlave *s)

>>   {

>>       SMBusDevice *dev = SMBUS_DEVICE(s);

>>       SMBusDeviceClass *sc = SMBUS_DEVICE_GET_CLASS(dev);

>> -    int ret;

>> +    uint8_t ret;

>>   

>>       switch (dev->mode) {

>>       case SMBUS_RECV_BYTE:

>> diff --git a/hw/input/lm832x.c b/hw/input/lm832x.c

>> index 74da30d9ca..9ae037953d 100644

>> --- a/hw/input/lm832x.c

>> +++ b/hw/input/lm832x.c

>> @@ -401,7 +401,7 @@ static int lm_i2c_event(I2CSlave *i2c, enum i2c_event event)

>>       return 0;

>>   }

>>   

>> -static int lm_i2c_rx(I2CSlave *i2c)

>> +static uint8_t lm_i2c_rx(I2CSlave *i2c)

>>   {

>>       LM823KbdState *s = LM8323(i2c);

>>   

>> diff --git a/hw/misc/pca9552.c b/hw/misc/pca9552.c

>> index 9775d5274a..7325d3f287 100644

>> --- a/hw/misc/pca9552.c

>> +++ b/hw/misc/pca9552.c

>> @@ -115,7 +115,7 @@ static void pca9552_autoinc(PCA9552State *s)

>>       }

>>   }

>>   

>> -static int pca9552_recv(I2CSlave *i2c)

>> +static uint8_t pca9552_recv(I2CSlave *i2c)

>>   {

>>       PCA9552State *s = PCA9552(i2c);

>>       uint8_t ret;

>> diff --git a/hw/misc/tmp105.c b/hw/misc/tmp105.c

>> index 0918f3a6ea..a4cae665b7 100644

>> --- a/hw/misc/tmp105.c

>> +++ b/hw/misc/tmp105.c

>> @@ -147,7 +147,7 @@ static void tmp105_write(TMP105State *s)

>>       }

>>   }

>>   

>> -static int tmp105_rx(I2CSlave *i2c)

>> +static uint8_t tmp105_rx(I2CSlave *i2c)

>>   {

>>       TMP105State *s = TMP105(i2c);

>>   

>> diff --git a/hw/misc/tmp421.c b/hw/misc/tmp421.c

>> index c234044305..a75eb994a8 100644

>> --- a/hw/misc/tmp421.c

>> +++ b/hw/misc/tmp421.c

>> @@ -249,7 +249,7 @@ static void tmp421_write(TMP421State *s)

>>       }

>>   }

>>   

>> -static int tmp421_rx(I2CSlave *i2c)

>> +static uint8_t tmp421_rx(I2CSlave *i2c)

>>   {

>>       TMP421State *s = TMP421(i2c);

>>   

>> diff --git a/hw/nvram/eeprom_at24c.c b/hw/nvram/eeprom_at24c.c

>> index 27cd01e615..d1456dafbd 100644

>> --- a/hw/nvram/eeprom_at24c.c

>> +++ b/hw/nvram/eeprom_at24c.c

>> @@ -74,10 +74,10 @@ int at24c_eeprom_event(I2CSlave *s, enum i2c_event event)

>>   }

>>   

>>   static

>> -int at24c_eeprom_recv(I2CSlave *s)

>> +uint8_t at24c_eeprom_recv(I2CSlave *s)

>>   {

>>       EEPROMState *ee = AT24C_EE(s);

>> -    int ret;

>> +    uint8_t ret;

>>   

>>       ret = ee->mem[ee->cur];

>>   

>> diff --git a/hw/timer/ds1338.c b/hw/timer/ds1338.c

>> index 3849b74a68..03da75486b 100644

>> --- a/hw/timer/ds1338.c

>> +++ b/hw/timer/ds1338.c

>> @@ -117,7 +117,7 @@ static int ds1338_event(I2CSlave *i2c, enum i2c_event event)

>>       return 0;

>>   }

>>   

>> -static int ds1338_recv(I2CSlave *i2c)

>> +static uint8_t ds1338_recv(I2CSlave *i2c)

>>   {

>>       DS1338State *s = DS1338(i2c);

>>       uint8_t res;

>> diff --git a/hw/timer/m41t80.c b/hw/timer/m41t80.c

>> index 734d7d95fc..c45b9297d8 100644

>> --- a/hw/timer/m41t80.c

>> +++ b/hw/timer/m41t80.c

>> @@ -40,7 +40,7 @@ static int m41t80_send(I2CSlave *i2c, uint8_t data)

>>       return 0;

>>   }

>>   

>> -static int m41t80_recv(I2CSlave *i2c)

>> +static uint8_t m41t80_recv(I2CSlave *i2c)

>>   {

>>       M41t80State *s = M41T80(i2c);

>>       struct tm now;

>> diff --git a/hw/timer/twl92230.c b/hw/timer/twl92230.c

>> index 3b43b46199..659b216dca 100644

>> --- a/hw/timer/twl92230.c

>> +++ b/hw/timer/twl92230.c

>> @@ -737,7 +737,7 @@ static int menelaus_tx(I2CSlave *i2c, uint8_t data)

>>       return 0;

>>   }

>>   

>> -static int menelaus_rx(I2CSlave *i2c)

>> +static uint8_t menelaus_rx(I2CSlave *i2c)

>>   {

>>       MenelausState *s = TWL92230(i2c);

>>   

>> diff --git a/include/hw/i2c/i2c.h b/include/hw/i2c/i2c.h

>> index 5dc166158b..75c5bd638b 100644

>> --- a/include/hw/i2c/i2c.h

>> +++ b/include/hw/i2c/i2c.h

>> @@ -33,10 +33,9 @@ typedef struct I2CSlaveClass {

>>   

>>       /*

>>        * Slave to master.  This cannot fail, the device should always

>> -     * return something here.  Negative values probably result in 0xff

>> -     * and a possible log from the driver, and shouldn't be used.

>> +     * return something here.

> Maybe use simple comment as "Master receives the data sent by the Slave"


I'm not sure I follow.  I think it's important to say that the device 
must return something,
Are you talking about the "Slave to master" part?

Thanks,

-corey


>>        */

>> -    int (*recv)(I2CSlave *s);

>> +    uint8_t (*recv)(I2CSlave *s);

>>   

>>       /*

>>        * Notify the slave of a bus state change.  For start event,

>> @@ -78,7 +77,7 @@ void i2c_end_transfer(I2CBus *bus);

>>   void i2c_nack(I2CBus *bus);

>>   int i2c_send_recv(I2CBus *bus, uint8_t *data, bool send);

>>   int i2c_send(I2CBus *bus, uint8_t data);

>> -int i2c_recv(I2CBus *bus);

>> +uint8_t i2c_recv(I2CBus *bus);

>>   

>>   DeviceState *i2c_create_slave(I2CBus *bus, const char *name, uint8_t addr);

>>   

> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>

>
diff mbox series

Patch

diff --git a/hw/arm/pxa2xx.c b/hw/arm/pxa2xx.c
index f598a1c053..3d7c88910e 100644
--- a/hw/arm/pxa2xx.c
+++ b/hw/arm/pxa2xx.c
@@ -1286,7 +1286,7 @@  static int pxa2xx_i2c_event(I2CSlave *i2c, enum i2c_event event)
     return 0;
 }
 
-static int pxa2xx_i2c_rx(I2CSlave *i2c)
+static uint8_t pxa2xx_i2c_rx(I2CSlave *i2c)
 {
     PXA2xxI2CSlaveState *slave = PXA2XX_I2C_SLAVE(i2c);
     PXA2xxI2CState *s = slave->host;
diff --git a/hw/arm/tosa.c b/hw/arm/tosa.c
index 7a925fa5e6..eef9d427e7 100644
--- a/hw/arm/tosa.c
+++ b/hw/arm/tosa.c
@@ -197,10 +197,10 @@  static int tosa_dac_event(I2CSlave *i2c, enum i2c_event event)
     return 0;
 }
 
-static int tosa_dac_recv(I2CSlave *s)
+static uint8_t tosa_dac_recv(I2CSlave *s)
 {
     printf("%s: recv not supported!!!\n", __func__);
-    return -1;
+    return 0xff;
 }
 
 static void tosa_tg_init(PXA2xxState *cpu)
diff --git a/hw/arm/z2.c b/hw/arm/z2.c
index 697a822f1e..6f18d924df 100644
--- a/hw/arm/z2.c
+++ b/hw/arm/z2.c
@@ -243,7 +243,7 @@  static int aer915_event(I2CSlave *i2c, enum i2c_event event)
     return 0;
 }
 
-static int aer915_recv(I2CSlave *slave)
+static uint8_t aer915_recv(I2CSlave *slave)
 {
     AER915State *s = AER915(slave);
     int retval = 0x00;
diff --git a/hw/audio/wm8750.c b/hw/audio/wm8750.c
index f4aa838f62..169b006ade 100644
--- a/hw/audio/wm8750.c
+++ b/hw/audio/wm8750.c
@@ -561,7 +561,7 @@  static int wm8750_tx(I2CSlave *i2c, uint8_t data)
     return 0;
 }
 
-static int wm8750_rx(I2CSlave *i2c)
+static uint8_t wm8750_rx(I2CSlave *i2c)
 {
     return 0x00;
 }
diff --git a/hw/display/sii9022.c b/hw/display/sii9022.c
index eaf11a6e7b..9994385c35 100644
--- a/hw/display/sii9022.c
+++ b/hw/display/sii9022.c
@@ -79,7 +79,7 @@  static int sii9022_event(I2CSlave *i2c, enum i2c_event event)
     return 0;
 }
 
-static int sii9022_rx(I2CSlave *i2c)
+static uint8_t sii9022_rx(I2CSlave *i2c)
 {
     sii9022_state *s = SII9022(i2c);
     uint8_t res = 0x00;
diff --git a/hw/display/ssd0303.c b/hw/display/ssd0303.c
index eb90ba26be..8edf34986c 100644
--- a/hw/display/ssd0303.c
+++ b/hw/display/ssd0303.c
@@ -62,10 +62,10 @@  typedef struct {
     uint8_t framebuffer[132*8];
 } ssd0303_state;
 
-static int ssd0303_recv(I2CSlave *i2c)
+static uint8_t ssd0303_recv(I2CSlave *i2c)
 {
     BADF("Reads not implemented\n");
-    return -1;
+    return 0xff;
 }
 
 static int ssd0303_send(I2CSlave *i2c, uint8_t data)
diff --git a/hw/gpio/max7310.c b/hw/gpio/max7310.c
index a560e3afd2..f35a930276 100644
--- a/hw/gpio/max7310.c
+++ b/hw/gpio/max7310.c
@@ -39,7 +39,7 @@  static void max7310_reset(DeviceState *dev)
     s->command = 0x00;
 }
 
-static int max7310_rx(I2CSlave *i2c)
+static uint8_t max7310_rx(I2CSlave *i2c)
 {
     MAX7310State *s = MAX7310(i2c);
 
diff --git a/hw/i2c/core.c b/hw/i2c/core.c
index b54725985a..15237ad073 100644
--- a/hw/i2c/core.c
+++ b/hw/i2c/core.c
@@ -191,23 +191,17 @@  int i2c_send_recv(I2CBus *bus, uint8_t *data, bool send)
         }
         return ret ? -1 : 0;
     } else {
-        if ((QLIST_EMPTY(&bus->current_devs)) || (bus->broadcast)) {
-            return -1;
-        }
-
-        sc = I2C_SLAVE_GET_CLASS(QLIST_FIRST(&bus->current_devs)->elt);
-        if (sc->recv) {
-            s = QLIST_FIRST(&bus->current_devs)->elt;
-            ret = sc->recv(s);
-            trace_i2c_recv(s->address, ret);
-            if (ret < 0) {
-                return ret;
-            } else {
-                *data = ret;
-                return 0;
+        ret = 0xff;
+        if (!QLIST_EMPTY(&bus->current_devs) && !bus->broadcast) {
+            sc = I2C_SLAVE_GET_CLASS(QLIST_FIRST(&bus->current_devs)->elt);
+            if (sc->recv) {
+                s = QLIST_FIRST(&bus->current_devs)->elt;
+                ret = sc->recv(s);
+                trace_i2c_recv(s->address, ret);
             }
         }
-        return -1;
+        *data = ret;
+        return 0;
     }
 }
 
@@ -216,12 +210,12 @@  int i2c_send(I2CBus *bus, uint8_t data)
     return i2c_send_recv(bus, &data, true);
 }
 
-int i2c_recv(I2CBus *bus)
+uint8_t i2c_recv(I2CBus *bus)
 {
-    uint8_t data;
-    int ret = i2c_send_recv(bus, &data, false);
+    uint8_t data = 0xff;
 
-    return ret < 0 ? ret : data;
+    i2c_send_recv(bus, &data, false);
+    return data;
 }
 
 void i2c_nack(I2CBus *bus)
diff --git a/hw/i2c/i2c-ddc.c b/hw/i2c/i2c-ddc.c
index be34fe072c..95325358db 100644
--- a/hw/i2c/i2c-ddc.c
+++ b/hw/i2c/i2c-ddc.c
@@ -51,7 +51,7 @@  static int i2c_ddc_event(I2CSlave *i2c, enum i2c_event event)
     return 0;
 }
 
-static int i2c_ddc_rx(I2CSlave *i2c)
+static uint8_t i2c_ddc_rx(I2CSlave *i2c)
 {
     I2CDDCState *s = I2CDDC(i2c);
 
diff --git a/hw/i2c/smbus_slave.c b/hw/i2c/smbus_slave.c
index 1e734752d7..549e7ae933 100644
--- a/hw/i2c/smbus_slave.c
+++ b/hw/i2c/smbus_slave.c
@@ -156,11 +156,11 @@  static int smbus_i2c_event(I2CSlave *s, enum i2c_event event)
     return 0;
 }
 
-static int smbus_i2c_recv(I2CSlave *s)
+static uint8_t smbus_i2c_recv(I2CSlave *s)
 {
     SMBusDevice *dev = SMBUS_DEVICE(s);
     SMBusDeviceClass *sc = SMBUS_DEVICE_GET_CLASS(dev);
-    int ret;
+    uint8_t ret;
 
     switch (dev->mode) {
     case SMBUS_RECV_BYTE:
diff --git a/hw/input/lm832x.c b/hw/input/lm832x.c
index 74da30d9ca..9ae037953d 100644
--- a/hw/input/lm832x.c
+++ b/hw/input/lm832x.c
@@ -401,7 +401,7 @@  static int lm_i2c_event(I2CSlave *i2c, enum i2c_event event)
     return 0;
 }
 
-static int lm_i2c_rx(I2CSlave *i2c)
+static uint8_t lm_i2c_rx(I2CSlave *i2c)
 {
     LM823KbdState *s = LM8323(i2c);
 
diff --git a/hw/misc/pca9552.c b/hw/misc/pca9552.c
index 9775d5274a..7325d3f287 100644
--- a/hw/misc/pca9552.c
+++ b/hw/misc/pca9552.c
@@ -115,7 +115,7 @@  static void pca9552_autoinc(PCA9552State *s)
     }
 }
 
-static int pca9552_recv(I2CSlave *i2c)
+static uint8_t pca9552_recv(I2CSlave *i2c)
 {
     PCA9552State *s = PCA9552(i2c);
     uint8_t ret;
diff --git a/hw/misc/tmp105.c b/hw/misc/tmp105.c
index 0918f3a6ea..a4cae665b7 100644
--- a/hw/misc/tmp105.c
+++ b/hw/misc/tmp105.c
@@ -147,7 +147,7 @@  static void tmp105_write(TMP105State *s)
     }
 }
 
-static int tmp105_rx(I2CSlave *i2c)
+static uint8_t tmp105_rx(I2CSlave *i2c)
 {
     TMP105State *s = TMP105(i2c);
 
diff --git a/hw/misc/tmp421.c b/hw/misc/tmp421.c
index c234044305..a75eb994a8 100644
--- a/hw/misc/tmp421.c
+++ b/hw/misc/tmp421.c
@@ -249,7 +249,7 @@  static void tmp421_write(TMP421State *s)
     }
 }
 
-static int tmp421_rx(I2CSlave *i2c)
+static uint8_t tmp421_rx(I2CSlave *i2c)
 {
     TMP421State *s = TMP421(i2c);
 
diff --git a/hw/nvram/eeprom_at24c.c b/hw/nvram/eeprom_at24c.c
index 27cd01e615..d1456dafbd 100644
--- a/hw/nvram/eeprom_at24c.c
+++ b/hw/nvram/eeprom_at24c.c
@@ -74,10 +74,10 @@  int at24c_eeprom_event(I2CSlave *s, enum i2c_event event)
 }
 
 static
-int at24c_eeprom_recv(I2CSlave *s)
+uint8_t at24c_eeprom_recv(I2CSlave *s)
 {
     EEPROMState *ee = AT24C_EE(s);
-    int ret;
+    uint8_t ret;
 
     ret = ee->mem[ee->cur];
 
diff --git a/hw/timer/ds1338.c b/hw/timer/ds1338.c
index 3849b74a68..03da75486b 100644
--- a/hw/timer/ds1338.c
+++ b/hw/timer/ds1338.c
@@ -117,7 +117,7 @@  static int ds1338_event(I2CSlave *i2c, enum i2c_event event)
     return 0;
 }
 
-static int ds1338_recv(I2CSlave *i2c)
+static uint8_t ds1338_recv(I2CSlave *i2c)
 {
     DS1338State *s = DS1338(i2c);
     uint8_t res;
diff --git a/hw/timer/m41t80.c b/hw/timer/m41t80.c
index 734d7d95fc..c45b9297d8 100644
--- a/hw/timer/m41t80.c
+++ b/hw/timer/m41t80.c
@@ -40,7 +40,7 @@  static int m41t80_send(I2CSlave *i2c, uint8_t data)
     return 0;
 }
 
-static int m41t80_recv(I2CSlave *i2c)
+static uint8_t m41t80_recv(I2CSlave *i2c)
 {
     M41t80State *s = M41T80(i2c);
     struct tm now;
diff --git a/hw/timer/twl92230.c b/hw/timer/twl92230.c
index 3b43b46199..659b216dca 100644
--- a/hw/timer/twl92230.c
+++ b/hw/timer/twl92230.c
@@ -737,7 +737,7 @@  static int menelaus_tx(I2CSlave *i2c, uint8_t data)
     return 0;
 }
 
-static int menelaus_rx(I2CSlave *i2c)
+static uint8_t menelaus_rx(I2CSlave *i2c)
 {
     MenelausState *s = TWL92230(i2c);
 
diff --git a/include/hw/i2c/i2c.h b/include/hw/i2c/i2c.h
index 5dc166158b..75c5bd638b 100644
--- a/include/hw/i2c/i2c.h
+++ b/include/hw/i2c/i2c.h
@@ -33,10 +33,9 @@  typedef struct I2CSlaveClass {
 
     /*
      * Slave to master.  This cannot fail, the device should always
-     * return something here.  Negative values probably result in 0xff
-     * and a possible log from the driver, and shouldn't be used.
+     * return something here.
      */
-    int (*recv)(I2CSlave *s);
+    uint8_t (*recv)(I2CSlave *s);
 
     /*
      * Notify the slave of a bus state change.  For start event,
@@ -78,7 +77,7 @@  void i2c_end_transfer(I2CBus *bus);
 void i2c_nack(I2CBus *bus);
 int i2c_send_recv(I2CBus *bus, uint8_t *data, bool send);
 int i2c_send(I2CBus *bus, uint8_t data);
-int i2c_recv(I2CBus *bus);
+uint8_t i2c_recv(I2CBus *bus);
 
 DeviceState *i2c_create_slave(I2CBus *bus, const char *name, uint8_t addr);