On 01/29/2013 06:23 PM, Rob Clark wrote:
Driver for the NXP TDA998X i2c hdmi encoder slave.
Rob, good to see a driver for TDA998x comming! I'd love to test it on CuBox (mach-dove) but there is no gpu driver I can hook up, yet. Anyway, I will make some comments how I think the driver should be improved.
diff --git a/drivers/gpu/drm/i2c/Kconfig b/drivers/gpu/drm/i2c/Kconfig index 1611836..4d341db 100644 --- a/drivers/gpu/drm/i2c/Kconfig +++ b/drivers/gpu/drm/i2c/Kconfig @@ -19,4 +19,10 @@ config DRM_I2C_SIL164 when used in pairs) TMDS transmitters, used in some nVidia video cards. +config DRM_I2C_NXP_TDA998X + tristate "NXP Semiconductors TDA998X HDMI encoder" + default m if DRM_TILCDC + help + Support for NXP Semiconductors TDA998X HDMI encoders.
Maybe nit-picking but later down you actually support TDA9989, TDA19988, and TDA19989. The latter ones don't fit in TDA998x, so at least the Kconfig entry should reflect TDA9989/TDA1998x.
[...] diff --git a/drivers/gpu/drm/i2c/tda998x_drv.c b/drivers/gpu/drm/i2c/tda998x_drv.c new file mode 100644 index 0000000..e68b58a --- /dev/null +++ b/drivers/gpu/drm/i2c/tda998x_drv.c @@ -0,0 +1,906 @@ +/* + * Copyright (C) 2012 Texas Instruments + * Author: Rob Clark<robdclark@xxxxxxxxx> + * + [...] + +/* The TDA9988 series of devices use a paged register scheme.. to simplify + * things we encode the page # in upper bits of the register #. To read/ + * write a given register, we need to make sure CURPAGE register is set + * appropriately. Which implies reads/writes are not atomic. Fun! + */
Please have a look at regmap-i2c, it also supports paged i2c registers and will save you _a lot_ of the i2c handling.
[...] + +/* Device versions: */ +#define TDA9989N2 0x0101 +#define TDA19989 0x0201 +#define TDA19989N2 0x0202 +#define TDA19988 0x0301
Maybe split this into device_version/revision? What does N2 stand for or is this the name NXP uses for that device? > [...]
+static void +cec_write(struct drm_encoder *encoder, uint16_t addr, uint8_t val) +{ + struct i2c_client *client = to_tda998x_priv(encoder)->cec; + uint8_t buf[] = {addr, val}; + int ret; + + ret = i2c_master_send(client, buf, ARRAY_SIZE(buf)); + if (ret< 0) + dev_err(&client->dev, "Error %d writing to cec:0x%x\n", ret, addr); +}
Has there been any decision on how to split/integrate cec from drm? Or is there display stuff located in cec i2c slave (I see HPD in ..._detect below)?
[...] +static void +tda998x_encoder_save(struct drm_encoder *encoder) +{ + DBG(""); +} + +static void +tda998x_encoder_restore(struct drm_encoder *encoder) +{ + DBG(""); +}
Hmmm, these DBG("") shouldn't be in upstream kernel code?
+static bool +tda998x_encoder_mode_fixup(struct drm_encoder *encoder, + const struct drm_display_mode *mode, + struct drm_display_mode *adjusted_mode) +{ + return true; +} + +static int +tda998x_encoder_mode_valid(struct drm_encoder *encoder, + struct drm_display_mode *mode) +{ + return MODE_OK; +}
At least a note would be helpful to see what callbacks are not yet done. I guess there will be some kind of mode check someday?
[...] +static enum drm_connector_status +tda998x_encoder_detect(struct drm_encoder *encoder, + struct drm_connector *connector) +{ + uint8_t val = cec_read(encoder, REG_CEC_RXSHPDLEV); + return (val& CEC_RXSHPDLEV_HPD) ? connector_status_connected : + connector_status_disconnected; +}
This is where cec slave gets called from hdmi i2c driver. Any chance there is HPD status in hdmi registers, too?
+/* I2C driver functions */ + +static int +tda998x_probe(struct i2c_client *client, const struct i2c_device_id *id) +{ + return 0; +} + +static int +tda998x_remove(struct i2c_client *client) +{ + return 0; +}
Hmm, empty _probe and _remove? Maybe these should get some code from _init below?
+static int +tda998x_encoder_init(struct i2c_client *client, + struct drm_device *dev, + struct drm_encoder_slave *encoder_slave) +{ + struct drm_encoder *encoder =&encoder_slave->base; + struct tda998x_priv *priv; + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->current_page = 0; + priv->cec = i2c_new_dummy(client->adapter, 0x34); + priv->dpms = DRM_MODE_DPMS_OFF; + + encoder_slave->slave_priv = priv; + encoder_slave->slave_funcs =&tda998x_encoder_funcs; + + /* wake up the device: */ + cec_write(encoder, REG_CEC_ENAMODS, + CEC_ENAMODS_EN_RXSENS | CEC_ENAMODS_EN_HDMI); + + tda998x_reset(encoder); + + /* read version: */ + priv->rev = reg_read(encoder, REG_VERSION_LSB) | + reg_read(encoder, REG_VERSION_MSB)<< 8; + + /* mask off feature bits: */ + priv->rev&= ~0x30; /* not-hdcp and not-scalar bit */
If revision register contains features, why not save them for later driver improvements?
+ switch (priv->rev) { + case TDA9989N2: dev_info(dev->dev, "found TDA9989 n2"); break; + case TDA19989: dev_info(dev->dev, "found TDA19989"); break; + case TDA19989N2: dev_info(dev->dev, "found TDA19989 n2"); break; + case TDA19988: dev_info(dev->dev, "found TDA19988"); break; + default: + DBG("found unsupported device: %04x", priv->rev); + goto fail; + }
I think printing revision is sufficient, no user will care about the actual device or revision.
+ /* after reset, enable DDC: */ + reg_write(encoder, REG_DDC_DISABLE, 0x00); + + /* set clock on DDC channel: */ + reg_write(encoder, REG_TX3, 39);
This should be kept disabled as long as there is no monitor attached (HPD!)
+ /* if necessary, disable multi-master: */ + if (priv->rev == TDA19989) + reg_set(encoder, REG_I2C_MASTER, I2C_MASTER_DIS_MM); + + cec_write(encoder, REG_CEC_FRO_IM_CLK_CTRL, + CEC_FRO_IM_CLK_CTRL_GHOST_DIS | CEC_FRO_IM_CLK_CTRL_IMCLK_SEL); + + return 0; + +fail: + /* if encoder_init fails, the encoder slave is never registered, + * so cleanup here: + */ + if (priv->cec) + i2c_unregister_device(priv->cec); + kfree(priv); + encoder_slave->slave_priv = NULL; + encoder_slave->slave_funcs = NULL; + return -ENXIO; +} + +static struct i2c_device_id tda998x_ids[] = { + { "tda998x", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, tda998x_ids);
Shouldn't the above carry the hdmi core i2c address at least?
+static struct drm_i2c_encoder_driver tda998x_driver = { + .i2c_driver = { + .probe = tda998x_probe, + .remove = tda998x_remove, + .driver = { + .name = "tda998x", + }, + .id_table = tda998x_ids, + }, + .encoder_init = tda998x_encoder_init, +}; + +/* Module initialization */ + +static int __init +tda998x_init(void) +{ + DBG(""); + return drm_i2c_encoder_register(THIS_MODULE,&tda998x_driver); +} + +static void __exit +tda998x_exit(void) +{ + DBG(""); + drm_i2c_encoder_unregister(&tda998x_driver); +} + +MODULE_AUTHOR("Rob Clark<robdclark@xxxxxxxxx"); +MODULE_DESCRIPTION("NXP Semiconductors TDA998X HDMI Encoder"); +MODULE_LICENSE("GPL");
Maybe stick to one version of "TDA998X" or "TDA998x" ? Regards, Sebastian -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html