From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ed1-f48.google.com (mail-ed1-f48.google.com [209.85.208.48]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 085F72F80 for ; Thu, 29 Apr 2021 08:25:57 +0000 (UTC) Received: by mail-ed1-f48.google.com with SMTP id s15so77567540edd.4 for ; Thu, 29 Apr 2021 01:25:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=iUQGD4uPM+aFQ386tGCMJIHR4xuNnFf3+z0KnOaljgs=; b=eOGCrfOLKtNCyZMT+1FMugK3ZEPyMyrDKQZq6BV4Od25GAaVmaUzZiI5T21VWL/osk FMTHzTBcxstK3CWm5dX7KzbwUEt9YMNrF5Z6fpiK3fkfPuy7V0egZI7FL1705h096XTI mub84LddnQzU3WOR6PmTi7t/z56Y/KR1GRdsLrPqVHFCZbt3CgItqJeu8VP7pOiIz/mc d/DAiq8iEAADPUTL3geFkutFX9JNYRpzSBe7gLDrKCcTc6eTyKXo/dKr/f+B24TV05+E pNEnqQETWONl5ewlgH30pykSn68ahKILS8g9FjaPDY1jT067oValeYERVp53ng6GHRQv LxEg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=iUQGD4uPM+aFQ386tGCMJIHR4xuNnFf3+z0KnOaljgs=; b=W/sbEFRRAcyHNiPxd/O++rVZn0nULAy0OhN7PftaccJld/vJExu1R5phDm1gG3cHJn qj9TMDRYCtcF4XBMweAVXTDuo4+yNv1bPqIPf1/vOwmgQMUZrQon3s5rTLN79fyt8aLt oH7dR5rhS3XcacXbv/ATB6Ggmyd6W+Y5coX8VWiLtwfbjF4BpECLVoGeNLqhTYJ5cKPv Sp9BAIvOV+4F0bekRIqWYPnVOz+VAMPIg3mX3N+in4RkrHJKyF3V5QMmKBqNUMnLoTZh 2IbT+uahQOvDT+q18pdGreJclC1Em0fUHDrTkZgZqGWpG4TGEgkr9TgS3Pn8R/+Z7jJX Z1Ow== X-Gm-Message-State: AOAM531vq734PsyfX4TePXIlKqqm/EIvYDePcGRjuO3Svwm3WDML3BQi jmHu9Z83eA1ZXqQiqaJypehuo8bKqtSrMw== X-Google-Smtp-Source: ABdhPJwr6nHgqdbfrDI/Af+DGLcN4CcxaEuXYAtfdbXJCxpMGadOmI2dR881+xA9g7vsZKNalVaaAw== X-Received: by 2002:a05:6402:34cd:: with SMTP id w13mr16696674edc.73.1619684756571; Thu, 29 Apr 2021 01:25:56 -0700 (PDT) Received: from agape.jhs ([5.171.81.14]) by smtp.gmail.com with ESMTPSA id dj7sm1758976edb.42.2021.04.29.01.25.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 29 Apr 2021 01:25:56 -0700 (PDT) Date: Thu, 29 Apr 2021 10:25:53 +0200 From: Fabio Aiuto To: "Fabio M. De Francesco" Cc: outreachy-kernel@googlegroups.com, Greg Kroah-Hartman , linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [Outreachy kernel] [PATCH 1/2] staging: rtl8723bs: hal: Remove set but unused variables Message-ID: <20210429082552.GC1409@agape.jhs> References: <20210428113346.28305-1-fmdefrancesco@gmail.com> <20210428113346.28305-2-fmdefrancesco@gmail.com> <20210429072619.GB1409@agape.jhs> <8266064.IJzC9MfcRG@linux.local> X-Mailing-List: linux-staging@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8266064.IJzC9MfcRG@linux.local> User-Agent: Mutt/1.10.1 (2018-07-13) On Thu, Apr 29, 2021 at 09:44:47AM +0200, Fabio M. De Francesco wrote: > On Thursday, April 29, 2021 9:26:20 AM CEST Fabio Aiuto wrote: > > Hi Fabio, > > > > On Wed, Apr 28, 2021 at 01:33:45PM +0200, Fabio M. De Francesco wrote: > > > Removed four set but unused variables. Issue detected by gcc. > > > > > > Signed-off-by: Fabio M. De Francesco > > > --- > > > > > > drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c | 5 ----- > > > 1 file changed, 5 deletions(-) > > > > > > diff --git a/drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c > > > b/drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c index > 082448557b53..96cb4426a0f4 > > > 100644 > > > --- a/drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c > > > +++ b/drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c > > > @@ -3900,14 +3900,11 @@ u8 GetHalDefVar8723B(struct adapter *padapter, > enum > > > hal_def_variable variable, v> > > > u32 cmd; > > > u32 ra_info1, ra_info2; > > > u32 rate_mask1, rate_mask2; > > > > > > - u8 curr_tx_rate, curr_tx_sgi, hight_rate, > lowest_rate; > > > > > > cmd = 0x40000100 | mac_id; > > > rtw_write32(padapter, > REG_HMEBOX_DBG_2_8723B, cmd); > > > msleep(10); > > > ra_info1 = rtw_read32(padapter, 0x2F0); > > > > > > - curr_tx_rate = ra_info1&0x7F; > > > - curr_tx_sgi = (ra_info1>>7)&0x01; > > > > > > cmd = 0x40000400 | mac_id; > > > rtw_write32(padapter, > REG_HMEBOX_DBG_2_8723B, cmd); > > > > > > @@ -3916,8 +3913,6 @@ u8 GetHalDefVar8723B(struct adapter *padapter, enum > > > hal_def_variable variable, v> > > > ra_info2 = rtw_read32(padapter, 0x2F4); > > > rate_mask1 = rtw_read32(padapter, 0x2F8); > > > rate_mask2 = rtw_read32(padapter, 0x2FC); > > > > > > - hight_rate = ra_info2&0xFF; > > > - lowest_rate = (ra_info2>>8) & 0xFF; > > > > > > } > > > break; > > > > rate_mask{1,2} and ra_info{1,2} seems to be unused as well. > > > > thank you, > > > > fabio > > > Hello Fabio, > > I'm not sure about it: rtw_read32 calls a pointer to a function. I'm don't > know drivers programming, however that function looks like an implementation > of a read() system call. So I wouldn't be so sure to remove those calls. > > Could calling a (*read) method have side effects on subsequent read()? I mean: > could it update some internal data structure? If not I can remove the > variables you mentioned above and the calls to read32. > > I'm looking forward to read your reply. > > Thanks, > > Fabio > > > hi Fabio, rtw_read32 is a macro wrapping _rtw_read32() defined as follows (in core/rtw_io.c): u32 _rtw_read32(struct adapter *adapter, u32 addr) { u32 r_val; /* struct io_queue *pio_queue = (struct io_queue *)adapter->pio_queue; */ struct io_priv *pio_priv = &adapter->iopriv; struct intf_hdl *pintfhdl = &(pio_priv->intf); u32 (*_read32)(struct intf_hdl *pintfhdl, u32 addr); _read32 = pintfhdl->io_ops._read32; r_val = _read32(pintfhdl, addr); return rtw_le32_to_cpu(r_val); } the actual read seems to be performed by the handler contained in pintfhdl->io_ops._read32; so: $ grep -r '\b_read32' drivers/staging/rtl8723bs/ drivers/staging/rtl8723bs/hal/sdio_ops.c: ops->_read32 = &sdio_read32; this is the place where _read32 is stored with sdio_read32 reference... drivers/staging/rtl8723bs/core/rtw_io.c: u32 (*_read32)(struct intf_hdl *pintfhdl, u32 addr); drivers/staging/rtl8723bs/core/rtw_io.c: _read32 = pintfhdl->io_ops._read32; ... if you check it in hal/sdio_ops.c, nothing is written, just reads are performed (and it's not odd, for a read function isn't supposed to write something under the hood ;)). I think those variables could be easily removed as W=1 gcc suggests. thank you, fabio