From 52775fd5b599c79e9a4152f75a6426bf376198dc Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Thu, 11 Apr 2013 10:59:12 -0300 Subject: [PATCH] [media] r820t: Allow disabling IMR callibration The rtl-sdr library disabled IMR callibration. While I'm not sure yet why, it could be a good idea to add a modprobe parameter here, to allow to also disable it. There are two rationale behind it: - It helps to compare USB dumps between rtl-sdr and the Kernel module; - If rtl-sdr disabled it, perhaps there's a good reason (e. g. it might not be actually working, or it might be causing some trouble). For both cases, it seems useful to add a modprobe parameter to allow testing the device with both configurations. Signed-off-by: Mauro Carvalho Chehab Tested-by: Antti Palosaari --- drivers/media/tuners/r820t.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) diff --git a/drivers/media/tuners/r820t.c b/drivers/media/tuners/r820t.c index 0125de897c8d..2e6a690ffb1a 100644 --- a/drivers/media/tuners/r820t.c +++ b/drivers/media/tuners/r820t.c @@ -56,6 +56,11 @@ static int debug; module_param(debug, int, 0644); MODULE_PARM_DESC(debug, "enable verbose debug messages"); +static int no_imr_cal; +module_param(no_imr_cal, int, 0444); +MODULE_PARM_DESC(no_imr_cal, "Disable IMR calibration at module init"); + + /* * enums and structures */ @@ -87,7 +92,8 @@ struct r820t_priv { u32 int_freq; u8 fil_cal_code; bool imr_done; - + bool has_lock; + bool init_done; struct r820t_sect_type imr_data[NUM_IMR]; /* Store current mode */ @@ -95,8 +101,6 @@ struct r820t_priv { enum v4l2_tuner_type type; v4l2_std_id std; u32 bw; /* in MHz */ - - bool has_lock; }; struct r820t_freq_range { @@ -1999,7 +2003,7 @@ static int r820t_imr_callibrate(struct r820t_priv *priv) int rc, i; int xtal_cap = 0; - if (priv->imr_done) + if (priv->init_done) return 0; /* Initialize registers */ @@ -2024,6 +2028,16 @@ static int r820t_imr_callibrate(struct r820t_priv *priv) priv->xtal_cap_sel = xtal_cap; } + /* + * Disables IMR callibration. That emulates the same behaviour + * as what is done by rtl-sdr userspace library. Useful for testing + */ + if (no_imr_cal) { + priv->init_done = true; + + return 0; + } + /* Initialize registers */ rc = r820t_write(priv, 0x05, r820t_init_array, sizeof(r820t_init_array)); @@ -2050,6 +2064,7 @@ static int r820t_imr_callibrate(struct r820t_priv *priv) if (rc < 0) return rc; + priv->init_done = true; priv->imr_done = true; return 0; -- 2.30.2