From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ED7182D2491; Wed, 27 Aug 2025 06:38:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756276697; cv=none; b=NtlPvpkg/WvErEGGDFTEAIiDX2lyrCWtd+Fi6Qoub/YES455VFdK0ncLCm2BfXynVFpG9paGcVG1Quth3b1QITPq3oGcPC5LxgjvwPFctI6Rd97T4I/UgdsqPD322xwq8taPYKVYuSpE1/ZwZgWtBi9bBQNArJOThDkM762oeTc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756276697; c=relaxed/simple; bh=ypbSldKKIg0u2TzSiWKfGcOi9083+yJHil2HF5x1BAI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=liEu6a6l0rx2oV3jml/Ec45XS+8So8/iwgdEm6IrHvCBgAew/XBNlmu7+MVKVD5mDMKK/m884M+39yXxuD36Vcc3fsCyl5CXnwgK7GNXHsWGpzF8wmmOaXJBPgjBtWF1iSFwg0wWsGTiLdegsMsZH96g8+GV1kVXXwUcI3bE6XY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=gZ5W3wfb; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="gZ5W3wfb" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 64274C4CEEB; Wed, 27 Aug 2025 06:38:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1756276695; bh=ypbSldKKIg0u2TzSiWKfGcOi9083+yJHil2HF5x1BAI=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=gZ5W3wfbNPKjXAR7FX8pd1xkVXDvLqgLQyWM2ndzAlBMZMaS6M3NB8bZpvIaAZlnI OH76UwiWwQbjkw+zv8qvKTSDCk56WBv4w/LSIM1Es5dqyxYEk1x5EUm+aXlpYU20Hk EI8T5G/SPxyGblUdzkQq4S1yafge4kPH8/RmIE4EExkL4mI15AT579pHGgXtRJXxAf MHLRQGmYoNzR0bQLcZ0cLRa5HzIRVQaBt9Be0WCFgFJiYKEL+Efp4XBCNvjf9r9VIC wYn6VJMG3+D7SZrMI17Y2QBq1ifG+V678WHQM/1HGnspuQakb1naBrV1YsPuQGzGs4 mMj1KwAeAaiHA== Message-ID: Date: Wed, 27 Aug 2025 08:38:09 +0200 Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 2/4] media: samsung: scaler: add scaler driver code To: Kisung Lee , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Alim Akhtar , Mauro Carvalho Chehab , Inki Dae Cc: dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-media@vger.kernel.org References: <20250827044720.3751272-1-kiisung.lee@samsung.com> <20250827044720.3751272-3-kiisung.lee@samsung.com> From: Krzysztof Kozlowski Content-Language: en-US Autocrypt: addr=krzk@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 27/08/2025 06:47, Kisung Lee wrote: > + > +static int sc_probe(struct platform_device *pdev) > +{ > + struct sc_dev *sc; > + struct resource *res; > + int ret = 0; > + size_t ivar; > + u32 hwver = 0; > + int irq_num; > + > + sc = devm_kzalloc(&pdev->dev, sizeof(struct sc_dev), GFP_KERNEL); Oh yeah, 10 year old coding style. Very dissapointing :( > + if (!sc) > + goto err_dev; > + > + sc->dev = &pdev->dev; > + spin_lock_init(&sc->ctxlist_lock); > + INIT_LIST_HEAD(&sc->ctx_list_high_prio); > + INIT_LIST_HEAD(&sc->ctx_list_low_prio); > + spin_lock_init(&sc->slock); > + mutex_init(&sc->lock); > + init_waitqueue_head(&sc->wait); > + > + sc->fence_context = dma_fence_context_alloc(1); > + spin_lock_init(&sc->fence_lock); > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + pr_err("Resource start: 0x%pa, end: 0x%pa, size: 0x%lx, flags: 0x%lx\n", No, drop. > + &res->start, &res->end, > + (unsigned long)resource_size(res), > + (unsigned long)res->flags); > + sc->regs = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(sc->regs)) { > + pr_err("devm_ioremap_resource failed: %pe\n", sc->regs); > + goto err_io_resource; > + } > + dma_set_mask(&pdev->dev, DMA_BIT_MASK(32)); > + > + atomic_set(&sc->wdt.cnt, 0); > + timer_setup(&sc->wdt.timer, sc_watchdog, 0); > + > + if (pdev->dev.of_node) { > + sc->dev_id = of_alias_get_id(pdev->dev.of_node, "scaler"); NAK, check my DT talk. > + if (sc->dev_id < 0) { > + dev_err(&pdev->dev, > + "Failed to read scaler node id(%d)!\n", sc->dev_id); > + ret = -EINVAL; > + goto err_node_id; > + } > + } else { > + sc->dev_id = pdev->id; > + } > + > + platform_set_drvdata(pdev, sc); > + > + pm_runtime_enable(&pdev->dev); > + > + ret = sc_populate_dt(sc); > + if (ret) > + goto err_dt; > + > + ret = sc_register_m2m_device(sc, sc->dev_id); > + if (ret) { > + dev_err(&pdev->dev, "failed to register m2m device\n"); > + goto err_m2m; > + } > + > +#if defined(CONFIG_PM_DEVFREQ) && defined(NEVER_DEFINED) You must be joking? > + if (!of_property_read_u32(pdev->dev.of_node, "mscl,int_qos_minlock", NAK > + (u32 *)&sc->qosreq_int_level)) { > + if (sc->qosreq_int_level > 0) { > + exynos_pm_qos_add_request(&sc->qosreq_int, > + PM_QOS_DEVICE_THROUGHPUT, 0); > + dev_info(&pdev->dev, "INT Min.Lock Freq. = %u\n", > + sc->qosreq_int_level); > + } > + } > +#endif > + if (of_property_read_u32(pdev->dev.of_node, "mscl,cfw", Cannot express more: NAK. You cannot add such undocumented ABI. > + (u32 *)&sc->cfw)) > + sc->cfw = 0; > + > + ret = sc_get_hwversion(sc); > + if (ret < 0) { > + dev_err(&pdev->dev, "%s: failed to get hw version (err %d)\n", > + __func__, ret); > + goto err_m2m; > + } else { > + hwver = ret; > + } > + > + for (ivar = 0; ivar < ARRAY_SIZE(sc_variant); ivar++) { > + if (sc->version >= sc_variant[ivar].version) { > + sc->variant = &sc_variant[ivar]; > + break; > + } > + } > + > + if (sc->version >= SCALER_VERSION(7, 0, 1)) { > + sc->sysreg_offset = SCALER_SYSREG_OFFSET(res->start); > + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); > + if (res) { > + sc->sysreg = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(sc->sysreg)) { > + dev_info(&pdev->dev, "SCALER LLC SYSREG is not setted.\n"); > + } else { > + writel(SCALER_LLC_NO_HINT, sc->sysreg + sc->sysreg_offset); > + dev_info(&pdev->dev, "SCALER LLC SYSREG is setted with NO_HINT.\n"); > + } > + } > + } > + > + sc_hwset_soft_reset(sc); > + > + if (!IS_ERR(sc->aclk)) > + clk_disable_unprepare(sc->aclk); > + if (!IS_ERR(sc->pclk)) > + clk_disable_unprepare(sc->pclk); > + pm_runtime_put(&pdev->dev); > + > + irq_num = platform_get_irq(pdev, 0); > + if (irq_num < 0) { > + dev_err(&pdev->dev, "failed to get IRQ resource\n"); you just upstream 10 year old code, right? Please carefully check the slides of my Monday's talk from OSSE25 about static analyzers. Look at slides about upstreaming 10 year old vendor code (that's a very bad idea). > + ret = -ENOENT; Wrong error code. > + goto err_get_irq_res; > + } > + > + ret = devm_request_irq(&pdev->dev, irq_num, sc_irq_handler, 0, > + pdev->name, sc); > + if (ret) { > + dev_err(&pdev->dev, "failed to install irq\n"); > + goto err_request_irq; > + } > + > + dev_info(&pdev->dev, > + "Driver probed successfully(version: %08x(%x))\n", > + hwver, sc->version); NAK, don't add such code. Ever. > + > + return 0; > + > +err_request_irq: > +err_get_irq_res: > +err_m2m: > +err_dt: > +err_node_id: > +err_io_resource: > + if (sc) > + devm_kfree(&pdev->dev, sc); > +err_dev: > + dev_err(&pdev->dev, > + "Driver probed failed!\n"); No, drop. Useless. > + > + return ret; > +} > + ... > +static struct sc_csc_tab sc_y2r = { > + /* REC.601 Narrow */ > + { 0x0254, 0x0000, 0x0331, 0x0254, 0xFF37, 0xFE60, 0x0254, 0x0409, 0x0000 }, > + /* REC.601 Wide */ > + { 0x0200, 0x0000, 0x02BE, 0x0200, 0xFF54, 0xFE9B, 0x0200, 0x0377, 0x0000 }, > + /* REC.709 Narrow */ > + { 0x0254, 0x0000, 0x0396, 0x0254, 0xFF93, 0xFEEF, 0x0254, 0x043A, 0x0000 }, > + /* REC.709 Wide */ > + { 0x0200, 0x0000, 0x0314, 0x0200, 0xFFA2, 0xFF16, 0x0200, 0x03A1, 0x0000 }, > + /* BT.2020 Narrow */ > + { 0x0254, 0x0000, 0x035B, 0x0254, 0xFFA0, 0xFEB3, 0x0254, 0x0449, 0x0000 }, > + /* BT.2020 Wide */ > + { 0x0200, 0x0000, 0x02E2, 0x0200, 0xFFAE, 0xFEE2, 0x0200, 0x03AE, 0x0000 }, > +}; > + > +static struct sc_csc_tab sc_r2y = { > + /* REC.601 Narrow */ > + { 0x0083, 0x0102, 0x0032, 0xFFB4, 0xFF6B, 0x00E1, 0x00E1, 0xFF44, 0xFFDB }, > + /* REC.601 Wide */ > + { 0x0099, 0x012D, 0x003A, 0xFFA8, 0xFF53, 0x0106, 0x0106, 0xFF25, 0xFFD5 }, > + /* REC.709 Narrow */ > + { 0x005D, 0x013A, 0x0020, 0xFFCC, 0xFF53, 0x00E1, 0x00E1, 0xFF34, 0xFFEB }, > + /* REC.709 Wide */ > + { 0x006D, 0x016E, 0x0025, 0xFFC4, 0xFF36, 0x0106, 0x0106, 0xFF12, 0xFFE8 }, > + /* BT.2020 Narrow */ > + { 0x0074, 0x012A, 0x001A, 0xFFC1, 0xFF5E, 0x00E1, 0x00E1, 0xFF31, 0xFFEE }, > + /* BT.2020 Wide */ > + { 0x0087, 0x015B, 0x001E, 0xFFB7, 0xFF43, 0x0106, 0x0106, 0xFF0F, 0xFFEB }, > +}; > + > +static struct sc_csc_tab *sc_csc_list[] = { > + [0] = &sc_no_csc, > + [1] = &sc_y2r, > + [2] = &sc_r2y, > +}; > + > +static struct sc_bl_op_val sc_bl_op_tbl[] = { Why absolutely nothing here is const? > + /* Sc, Sa, Dc, Da */ > + {ZERO, ZERO, ZERO, ZERO}, /* CLEAR */ > + { ONE, ONE, ZERO, ZERO}, /* SRC */ > + {ZERO, ZERO, ONE, ONE}, /* DST */ > + { ONE, ONE, INV_SA, INV_SA}, /* SRC_OVER */ > + {INV_DA, ONE, ONE, INV_SA}, /* DST_OVER */ > + {DST_A, DST_A, ZERO, ZERO}, /* SRC_IN */ > + {ZERO, ZERO, SRC_A, SRC_A}, /* DST_IN */ > + {INV_DA, INV_DA, ZERO, ZERO}, /* SRC_OUT */ > + {ZERO, ZERO, INV_SA, INV_SA}, /* DST_OUT */ > + {DST_A, ZERO, INV_SA, ONE}, /* SRC_ATOP */ > + {INV_DA, ONE, SRC_A, ZERO}, /* DST_ATOP */ > + {INV_DA, ONE, INV_SA, ONE}, /* XOR: need to WA */ > + {INV_DA, ONE, INV_SA, INV_SA}, /* DARKEN */ > + {INV_DA, ONE, INV_SA, INV_SA}, /* LIGHTEN */ > + {INV_DA, ONE, INV_SA, INV_SA}, /* MULTIPLY */ > + {ONE, ONE, INV_SC, INV_SA}, /* SCREEN */ > + {ONE, ONE, ONE, ONE}, /* ADD */ > +}; > + ... > + yfilter = sc_get_scale_filter(yratio); > + cfilter = sc_get_scale_filter(cratio); > + bit_adj = !sc->variant->pixfmt_10bit; > + > + /* reset value of the coefficient registers are the 8:8 table */ > + for (phase = 0; phase < 9; phase++) { > + __raw_writel(sc_coef_adj(bit_adj, sc_coef_4t[yfilter][phase][1]), > + sc->regs + SCALER_YVCOEF + phase * 8); > + __raw_writel(sc_coef_adj(bit_adj, sc_coef_4t[yfilter][phase][0]), > + sc->regs + SCALER_YVCOEF + phase * 8 + 4); > + } > + > + for (phase = 0; phase < 9; phase++) { > + __raw_writel(sc_coef_adj(bit_adj, sc_coef_4t[cfilter][phase][1]), > + sc->regs + SCALER_CVCOEF + phase * 8); > + __raw_writel(sc_coef_adj(bit_adj, sc_coef_4t[cfilter][phase][0]), > + sc->regs + SCALER_CVCOEF + phase * 8 + 4); > + } > +} > + > +void sc_get_span(struct sc_frame *frame, u32 *yspan, u32 *cspan) > +{ > + if (IS_ERR_OR_NULL(frame) || IS_ERR_OR_NULL(yspan) || IS_ERR_OR_NULL(cspan)) { Sorrry, but what? How each of these can be ERR or NULL? How is it possible? Please provide exact cases leading to this. > + pr_err("[%s] frame(%p) or yspan(%p) or cspan(%p) is wrong\n", > + __func__, frame, yspan, cspan); > + return; > + } > + > + *yspan = frame->width; > + > + if (frame->sc_fmt->num_comp == 2) { > + *cspan = frame->width << frame->sc_fmt->cspan; > + } else if (frame->sc_fmt->num_comp == 3) { > + if (sc_fmt_is_ayv12(frame->sc_fmt->pixelformat)) { > + *cspan = ALIGN(frame->width >> 1, 16); > + } else if (sc_fmt_is_yuv420(frame->sc_fmt->pixelformat)) { /* YUV420 */ > + if (frame->cspanalign) { > + *cspan = ALIGN(frame->width >> 1, > + 8 << (frame->cspanalign - 1)); > + } else { > + *cspan = frame->width >> 1; > + } > + } else if (frame->sc_fmt->cspan) { /* YUV444 */ > + *cspan = frame->width; > + } else { > + *cspan = frame->width >> 1; > + } > + } else if (frame->sc_fmt->num_comp == 1) { > + if (sc_fmt_is_rgb888(frame->sc_fmt->pixelformat)) > + if (frame->yspanalign) > + *yspan = ALIGN(frame->width, > + 8 << (frame->yspanalign - 1)); > + *cspan = 0; > + } else { > + *cspan = 0; > + } > +} > + > +void sc_hwset_src_imgsize(struct sc_dev *sc, struct sc_frame *frame) > +{ > + u32 yspan = 0, cspan = 0; > + > + if (IS_ERR_OR_NULL(sc) || IS_ERR_OR_NULL(frame)) { How can be ERR or NULL? This looks buggy, like you don't know flow of own code. > + pr_err("[%s] sc(%p) or frame(%p) is wrong\n", __func__, sc, frame); dev_err This is terrible driver, poorly coded, using 10 year old coding style, repeating many known antipatterns and mistakes. It is very dissapointing to see Samsung sending such poor code. Really poor code. Best regards, Krzysztof