From 0de8e3533e08745616a30bdb3fa5106c85083e51 Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Mon, 8 Feb 2010 20:30:33 -0300 Subject: [PATCH] V4L/DVB: dib3000mc: reduce large stack usage This patch reduces static stack usage of one of the 2 top offenders as listed by 'make checkstack': Building with CONFIG_FRAME_WARN=2048 produces: drivers/media/dvb/frontends/dib3000mc.c:853: warning: the frame size of 2224 bytes is larger than 2048 bytes and in 'make checkstack', the stack usage goes from: 0x00000bbd dib3000mc_i2c_enumeration [dib3000mc]: 2232 to unlisted with this patch. I don't have the hardware that is needed to test this patch. Signed-off-by: Randy Dunlap Signed-off-by: Andrew Morton Acked-by: Patrick Boettcher Signed-off-by: Mauro Carvalho Chehab --- drivers/media/dvb/frontends/dib3000mc.c | 35 +++++++++++++++++++++------------ 1 file changed, 22 insertions(+), 13 deletions(-) diff --git a/drivers/media/dvb/frontends/dib3000mc.c b/drivers/media/dvb/frontends/dib3000mc.c index 40a0998..afad252 100644 --- a/drivers/media/dvb/frontends/dib3000mc.c +++ b/drivers/media/dvb/frontends/dib3000mc.c @@ -814,42 +814,51 @@ EXPORT_SYMBOL(dib3000mc_set_config); int dib3000mc_i2c_enumeration(struct i2c_adapter *i2c, int no_of_demods, u8 default_addr, struct dib3000mc_config cfg[]) { - struct dib3000mc_state st = { .i2c_adap = i2c }; + struct dib3000mc_state *dmcst; int k; u8 new_addr; static u8 DIB3000MC_I2C_ADDRESS[] = {20,22,24,26}; + dmcst = kzalloc(sizeof(struct dib3000mc_state), GFP_KERNEL); + if (dmcst == NULL) + return -ENODEV; + + dmcst->i2c_adap = i2c; + for (k = no_of_demods-1; k >= 0; k--) { - st.cfg = &cfg[k]; + dmcst->cfg = &cfg[k]; /* designated i2c address */ new_addr = DIB3000MC_I2C_ADDRESS[k]; - st.i2c_addr = new_addr; - if (dib3000mc_identify(&st) != 0) { - st.i2c_addr = default_addr; - if (dib3000mc_identify(&st) != 0) { + dmcst->i2c_addr = new_addr; + if (dib3000mc_identify(dmcst) != 0) { + dmcst->i2c_addr = default_addr; + if (dib3000mc_identify(dmcst) != 0) { dprintk("-E- DiB3000P/MC #%d: not identified\n", k); + kfree(dmcst); return -ENODEV; } } - dib3000mc_set_output_mode(&st, OUTMODE_MPEG2_PAR_CONT_CLK); + dib3000mc_set_output_mode(dmcst, OUTMODE_MPEG2_PAR_CONT_CLK); // set new i2c address and force divstr (Bit 1) to value 0 (Bit 0) - dib3000mc_write_word(&st, 1024, (new_addr << 3) | 0x1); - st.i2c_addr = new_addr; + dib3000mc_write_word(dmcst, 1024, (new_addr << 3) | 0x1); + dmcst->i2c_addr = new_addr; } for (k = 0; k < no_of_demods; k++) { - st.cfg = &cfg[k]; - st.i2c_addr = DIB3000MC_I2C_ADDRESS[k]; + dmcst->cfg = &cfg[k]; + dmcst->i2c_addr = DIB3000MC_I2C_ADDRESS[k]; - dib3000mc_write_word(&st, 1024, st.i2c_addr << 3); + dib3000mc_write_word(dmcst, 1024, dmcst->i2c_addr << 3); /* turn off data output */ - dib3000mc_set_output_mode(&st, OUTMODE_HIGH_Z); + dib3000mc_set_output_mode(dmcst, OUTMODE_HIGH_Z); } + + kfree(dmcst); return 0; } EXPORT_SYMBOL(dib3000mc_i2c_enumeration); -- 1.8.2.3