From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from acsinet12.oracle.com ([141.146.126.234]:16491 "EHLO acsinet12.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752278Ab0BHXcQ (ORCPT ); Mon, 8 Feb 2010 18:32:16 -0500 Message-ID: <4B709EA4.6020408@oracle.com> Date: Mon, 08 Feb 2010 15:30:44 -0800 From: Randy Dunlap MIME-Version: 1.0 To: linux-media@vger.kernel.org, Mauro Carvalho Chehab CC: Patrick Boettcher , Andrew Morton Subject: [PATCH] dib7000p: reduce large stack usage Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: From: Randy Dunlap 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/dib7000p.c:1367: warning: the frame size of 2320 bytes is larger than 2048 bytes and in 'make checkstack', the stack usage goes from: 0x00002409 dib7000p_i2c_enumeration [dib7000p]: 2328 to unlisted with this patch. Also change one caller of dib7000p_i2c_enumeration() to check its return value. I don't have the hardware that is needed to test this patch. Signed-off-by: Randy Dunlap Cc: Patrick Boettcher --- drivers/media/dvb/dvb-usb/cxusb.c | 5 +-- drivers/media/dvb/frontends/dib7000p.c | 36 ++++++++++++++--------- 2 files changed, 25 insertions(+), 16 deletions(-) --- lnx-2633-rc7.orig/drivers/media/dvb/dvb-usb/cxusb.c +++ lnx-2633-rc7/drivers/media/dvb/dvb-usb/cxusb.c @@ -1024,8 +1024,9 @@ static int cxusb_dualdig4_rev2_frontend_ cxusb_bluebird_gpio_pulse(adap->dev, 0x02, 1); - dib7000p_i2c_enumeration(&adap->dev->i2c_adap, 1, 18, - &cxusb_dualdig4_rev2_config); + if (dib7000p_i2c_enumeration(&adap->dev->i2c_adap, 1, 18, + &cxusb_dualdig4_rev2_config) < 0) + return -ENODEV; adap->fe = dvb_attach(dib7000p_attach, &adap->dev->i2c_adap, 0x80, &cxusb_dualdig4_rev2_config); --- lnx-2633-rc7.orig/drivers/media/dvb/frontends/dib7000p.c +++ lnx-2633-rc7/drivers/media/dvb/frontends/dib7000p.c @@ -1323,46 +1323,54 @@ EXPORT_SYMBOL(dib7000p_pid_filter); int dib7000p_i2c_enumeration(struct i2c_adapter *i2c, int no_of_demods, u8 default_addr, struct dib7000p_config cfg[]) { - struct dib7000p_state st = { .i2c_adap = i2c }; + struct dib7000p_state *dpst; int k = 0; u8 new_addr = 0; + dpst = kzalloc(sizeof(struct dib7000p_state), GFP_KERNEL); + if (!dpst) + return -ENODEV; + + dpst->i2c_adap = i2c; + for (k = no_of_demods-1; k >= 0; k--) { - st.cfg = cfg[k]; + dpst->cfg = cfg[k]; /* designated i2c address */ new_addr = (0x40 + k) << 1; - st.i2c_addr = new_addr; - dib7000p_write_word(&st, 1287, 0x0003); /* sram lead in, rdy */ - if (dib7000p_identify(&st) != 0) { - st.i2c_addr = default_addr; - dib7000p_write_word(&st, 1287, 0x0003); /* sram lead in, rdy */ - if (dib7000p_identify(&st) != 0) { + dpst->i2c_addr = new_addr; + dib7000p_write_word(dpst, 1287, 0x0003); /* sram lead in, rdy */ + if (dib7000p_identify(dpst) != 0) { + dpst->i2c_addr = default_addr; + dib7000p_write_word(dpst, 1287, 0x0003); /* sram lead in, rdy */ + if (dib7000p_identify(dpst) != 0) { dprintk("DiB7000P #%d: not identified\n", k); + kfree(dpst); return -EIO; } } /* start diversity to pull_down div_str - just for i2c-enumeration */ - dib7000p_set_output_mode(&st, OUTMODE_DIVERSITY); + dib7000p_set_output_mode(dpst, OUTMODE_DIVERSITY); /* set new i2c address and force divstart */ - dib7000p_write_word(&st, 1285, (new_addr << 2) | 0x2); + dib7000p_write_word(dpst, 1285, (new_addr << 2) | 0x2); dprintk("IC %d initialized (to i2c_address 0x%x)", k, new_addr); } for (k = 0; k < no_of_demods; k++) { - st.cfg = cfg[k]; - st.i2c_addr = (0x40 + k) << 1; + dpst->cfg = cfg[k]; + dpst->i2c_addr = (0x40 + k) << 1; // unforce divstr - dib7000p_write_word(&st, 1285, st.i2c_addr << 2); + dib7000p_write_word(dpst, 1285, dpst->i2c_addr << 2); /* deactivate div - it was just for i2c-enumeration */ - dib7000p_set_output_mode(&st, OUTMODE_HIGH_Z); + dib7000p_set_output_mode(dpst, OUTMODE_HIGH_Z); } + kfree(dpst); return 0; } EXPORT_SYMBOL(dib7000p_i2c_enumeration);